Help needed with 82 Crossfire
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thank you.. I’m almost to the point of testing the valve train as you suggested.
Yesterday I explained the situation to a friend who has been and owns a service center for a very long time. He also suggested possible valve train issue. He suggested testing by pressurizing each cylinder with 30psi and listening for air leak via intake, exhaust, crankcase. What’s the thought on this test procedure to test for a valve train problem?
thanks again..
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Hard drive recovery info
WOW! Somewhat crazy issue...What did you do last before you had this issue or did it just happen out of the blue and you did nothing? Odd issue and it does sound like a mechanical issue since no CEL. Whatever it is, the ECM seems to be happy with it. Balance comes to mind here since your TPS is way off and cannot be adjusted properly. It is possible that you have multiple issues going on here.
As mentioned, I would have a very careful examination of the valvetrain, you may find that something is amiss or a cam lobe issue. If one or two valves are lower than the others opening, you have a cam lobe issue which would be bad of course. Use a dial indicator to make an accurate check. Since it is very hard to hear the issue in your vid, but the tic tic is not normal for sure but could easily be a lifter issue also. That would have nothing to do with your TPS issue though. You also mentioned I think in the beginning that your vacuum was low. According to your gauge at idle, 18 is not really low. 18-21 would be in the normal range IMO, 14 or less would be low and undrivable with power brakes, unless you really don't want to stop. Keep posting up things done and checked, you will find the issue. GL
Also, if anyone is interested, I spent the entire day at Dynamic EFI. WOW! So much stuff, more than I ever anticipated. We went through a lot and there is still a little more to go through. One of the hangups is the firmware and software source code. We made image copies of the HD (which was an old spinner drive running XP) We are going to try to hack the drive and get it to boot into the desktop which I think we can do it. I also need the Gerber files for the board build. Found tons of chips, solder masks, lots of ECMs, drawings and schematics and much more. In the end it is a move in the right direction, but will take a bit longer than I thought. Just a small update.
As mentioned, I would have a very careful examination of the valvetrain, you may find that something is amiss or a cam lobe issue. If one or two valves are lower than the others opening, you have a cam lobe issue which would be bad of course. Use a dial indicator to make an accurate check. Since it is very hard to hear the issue in your vid, but the tic tic is not normal for sure but could easily be a lifter issue also. That would have nothing to do with your TPS issue though. You also mentioned I think in the beginning that your vacuum was low. According to your gauge at idle, 18 is not really low. 18-21 would be in the normal range IMO, 14 or less would be low and undrivable with power brakes, unless you really don't want to stop. Keep posting up things done and checked, you will find the issue. GL
Also, if anyone is interested, I spent the entire day at Dynamic EFI. WOW! So much stuff, more than I ever anticipated. We went through a lot and there is still a little more to go through. One of the hangups is the firmware and software source code. We made image copies of the HD (which was an old spinner drive running XP) We are going to try to hack the drive and get it to boot into the desktop which I think we can do it. I also need the Gerber files for the board build. Found tons of chips, solder masks, lots of ECMs, drawings and schematics and much more. In the end it is a move in the right direction, but will take a bit longer than I thought. Just a small update.
Thanks again Buccaneer.. I’ll get back to you on my issue shortly but since computer support is my thing I thought I’d just mention this based on your post about the hard drive.. And of course you might already know this but just in case..
As long as the hard drive and files are not corrupted the easiest and quickest thing you can do is get an external drive adapter to accommodate the type of hd interface it has to usb. This way you can start by just seeing if the files are accessible using another windows computer. If they are of course you can just copy them to another drive to open or test them.
The reason I say this would be a good first step is it eliminates the need to fix the boot partition and worry about getting it to boot XP.
For instance this or something similar.
Good luck!
Racer
Joined: Aug 2015
Posts: 384
Likes: 144
From: Pine Ridge FL
Yes, it's a long shot you'll see a difference but figure it's an easy test. I'm still leaning towards an ignition issue because I figured you'd see a bouncing vacuum gauge if you had a valve issue. But I may be wrong so please keep us posted, I am very curious at this point.
Safety Car
Joined: Nov 2005
Posts: 3,532
Likes: 1,185
From: Arizona - If you don’t know CFI, STOP proliferating the myths around it...
Thanks again Buccaneer.. I’ll get back to you on my issue shortly but since computer support is my thing I thought I’d just mention this based on your post about the hard drive.. And of course you might already know this but just in case..
As long as the hard drive and files are not corrupted the easiest and quickest thing you can do is get an external drive adapter to accommodate the type of hd interface it has to usb. This way you can start by just seeing if the files are accessible using another windows computer. If they are of course you can just copy them to another drive to open or test them.
The reason I say this would be a good first step is it eliminates the need to fix the boot partition and worry about getting it to boot XP.
For instance this or something similar.
https://www.amazon.com/Sabrent-Exter...1zcF9tdGY&th=1
Good luck!
As long as the hard drive and files are not corrupted the easiest and quickest thing you can do is get an external drive adapter to accommodate the type of hd interface it has to usb. This way you can start by just seeing if the files are accessible using another windows computer. If they are of course you can just copy them to another drive to open or test them.
The reason I say this would be a good first step is it eliminates the need to fix the boot partition and worry about getting it to boot XP.
For instance this or something similar.
https://www.amazon.com/Sabrent-Exter...1zcF9tdGY&th=1
Good luck!
Thanks again Buccaneer.. I’ll get back to you on my issue shortly but since computer support is my thing I thought I’d just mention this based on your post about the hard drive.. And of course you might already know this but just in case..
As long as the hard drive and files are not corrupted the easiest and quickest thing you can do is get an external drive adapter to accommodate the type of hd interface it has to usb. This way you can start by just seeing if the files are accessible using another windows computer. If they are of course you can just copy them to another drive to open or test them.
The reason I say this would be a good first step is it eliminates the need to fix the boot partition and worry about getting it to boot XP.
For instance this or something similar.
As long as the hard drive and files are not corrupted the easiest and quickest thing you can do is get an external drive adapter to accommodate the type of hd interface it has to usb. This way you can start by just seeing if the files are accessible using another windows computer. If they are of course you can just copy them to another drive to open or test them.
The reason I say this would be a good first step is it eliminates the need to fix the boot partition and worry about getting it to boot XP.
For instance this or something similar.
Oh yeah, I already copied the original image to an SSD to preserve the data since that spinner could go south on us. Verified that the image was good and accessible. Dynamic EFI has to remove all private data by file and then we will hack XP and boot XP to the desktop which we should be able to do. It will be a lot easier IMO to find the apps used like MS Visual Studio that more than likely was used to write the C++ source code along with other apps for the board like OrCAD which I think he used. Without these files, there is nothing, and the EBL is done and gone.
I also had a meeting this morning with a foundry management about the manifold and was a VERY productive meeting. When I get back to AZ, I will be sending them some docs and see what they can quote me. There is hope on that project again as well.
Burning Brakes
Joined: Feb 2020
Posts: 904
Likes: 569
From: Central NJ
I already copied the original image to an SSD to preserve the data since that spinner could go south on us. Verified that the image was good and accessible.
Not sure what kind of image you have made but you might consider spinning up an XP VM on your PC using Hyper V or similar. Then try restoring/importing the image to it using something like Macrium Reflect or Acronis... Just spit balling here....
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Last edited by 1860army; Jun 30, 2025 at 09:28 PM.
Drifting
Joined: Dec 2016
Posts: 1,387
Likes: 220
Good morning..
Thanks again for everyone’s latest thoughts, please keep them coming..
Update. Installed new TPS. It is the same as the original. Meaning I have to force it to the maximum physical setting and I still can’t get the .525 volt reading. But if I open the throttle it goes up to .525 and sweeps all the way to 2-4 volts ( sorry I did not remember the exact voltage. One theory I have is that the computer uses that base voltage of .525 as the known position of the throttle fully closed and maybe being able to only get .4 something throws the whole range off??
I assure you that it is a pop not a knock. I can tell that by the snap of the sound and when it occurs when I blip the throttle . In other words It happens when I blip it in park but the engine has not yet increased rpm. I hope this new video shows that better. Notice that the engine rpms aren’t changing yet we hear the pop.
tested the MAP with manual vacuum and it seems to act correctly and how the manual says it should.
Thanks again! I appreciate your help..
Thanks again for everyone’s latest thoughts, please keep them coming..
Update. Installed new TPS. It is the same as the original. Meaning I have to force it to the maximum physical setting and I still can’t get the .525 volt reading. But if I open the throttle it goes up to .525 and sweeps all the way to 2-4 volts ( sorry I did not remember the exact voltage. One theory I have is that the computer uses that base voltage of .525 as the known position of the throttle fully closed and maybe being able to only get .4 something throws the whole range off??
I assure you that it is a pop not a knock. I can tell that by the snap of the sound and when it occurs when I blip the throttle . In other words It happens when I blip it in park but the engine has not yet increased rpm. I hope this new video shows that better. Notice that the engine rpms aren’t changing yet we hear the pop.
tested the MAP with manual vacuum and it seems to act correctly and how the manual says it should.
Thanks again! I appreciate your help..
Thread Starter
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Joined: Aug 2000
Posts: 62
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Hello everyone,
Sorry I didn’t want to go dark but I had to concentrate on a work project and also I have the car at a location a little ways from home so can’t work on it everyday.
Thanks again for your help, non improvements yet.
Sorry I didn’t want to go dark but I had to concentrate on a work project and also I have the car at a location a little ways from home so can’t work on it everyday.
Thanks again for your help, non improvements yet.
Thread Starter
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Joined: Aug 2000
Posts: 62
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I’m going to research the aldl cable. I have some familiarity with the Toyota equivalent so I have some idea about it.
For the 82 vette what would I need? Cable, computer, and what software?
Thanks again for your help, much appreciated.
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Thread Starter
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Posts: 62
Likes: 2
WOW! Somewhat crazy issue...What did you do last before you had this issue or did it just happen out of the blue and you did nothing? Odd issue and it does sound like a mechanical issue since no CEL. Whatever it is, the ECM seems to be happy with it. Balance comes to mind here since your TPS is way off and cannot be adjusted properly. It is possible that you have multiple issues going on here.
As mentioned, I would have a very careful examination of the valvetrain, you may find that something is amiss or a cam lobe issue. If one or two valves are lower than the others opening, you have a cam lobe issue which would be bad of course. Use a dial indicator to make an accurate check. Since it is very hard to hear the issue in your vid, but the tic tic is not normal for sure but could easily be a lifter issue also. That would have nothing to do with your TPS issue though. You also mentioned I think in the beginning that your vacuum was low. According to your gauge at idle, 18 is not really low. 18-21 would be in the normal range IMO, 14 or less would be low and undrivable with power brakes, unless you really don't want to stop. Keep posting up things done and checked, you will find the issue. GL
Also, if anyone is interested, I spent the entire day at Dynamic EFI. WOW! So much stuff, more than I ever anticipated. We went through a lot and there is still a little more to go through. One of the hangups is the firmware and software source code. We made image copies of the HD (which was an old spinner drive running XP) We are going to try to hack the drive and get it to boot into the desktop which I think we can do it. I also need the Gerber files for the board build. Found tons of chips, solder masks, lots of ECMs, drawings and schematics and much more. In the end it is a move in the right direction, but will take a bit longer than I thought. Just a small update.
As mentioned, I would have a very careful examination of the valvetrain, you may find that something is amiss or a cam lobe issue. If one or two valves are lower than the others opening, you have a cam lobe issue which would be bad of course. Use a dial indicator to make an accurate check. Since it is very hard to hear the issue in your vid, but the tic tic is not normal for sure but could easily be a lifter issue also. That would have nothing to do with your TPS issue though. You also mentioned I think in the beginning that your vacuum was low. According to your gauge at idle, 18 is not really low. 18-21 would be in the normal range IMO, 14 or less would be low and undrivable with power brakes, unless you really don't want to stop. Keep posting up things done and checked, you will find the issue. GL
Also, if anyone is interested, I spent the entire day at Dynamic EFI. WOW! So much stuff, more than I ever anticipated. We went through a lot and there is still a little more to go through. One of the hangups is the firmware and software source code. We made image copies of the HD (which was an old spinner drive running XP) We are going to try to hack the drive and get it to boot into the desktop which I think we can do it. I also need the Gerber files for the board build. Found tons of chips, solder masks, lots of ECMs, drawings and schematics and much more. In the end it is a move in the right direction, but will take a bit longer than I thought. Just a small update.
Sorry for my delayed reply..
The car gets started or driven very little. One day a while ago it started and had an unusualy high idle. If I remember correctly that high idle didnt last long and maybe just happened a time or 2 after that. I believe it was around that time that I started getting the popping sound when reving or accelerating. I didnt not make any changes around that time that the issue started. The thing I did prior and it could be years (but little miles) earlier was the plugs and wires. Just a reminder but just a week or so ago I did brand new plugs and confirmed the resistance of each plug wire.
Vacuum is still around 17-18 and steady. The reason I used the term low is that the guage I am using has the bottom of the normal range / green area at 17 so I thought of that as low.
Many smart people including yourself has mentioned the valvetrain so It’s probably time for me to work on that. Your technique is easy for me to picture. I just wonder how and how easy it is to turn the engine over by hand.
What do you think about that other technique of putting 30psi in the cylinder and listening to the intake, exhaust and crankcase to see if a leak is present, what to you think of that test?
Thank you and have a good evening!
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Yes, it's a long shot you'll see a difference but figure it's an easy test. I'm still leaning towards an ignition issue because I figured you'd see a bouncing vacuum gauge if you had a valve issue. But I may be wrong so please keep us posted, I am very curious at this point.
Thanks again.. Have a happy 4th !
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Quick update..
Yesterday.
-Forced the TPS to read .525 at closed throttle position. Issue remains the same.
Will work on testing the valve train next. Will post any updates.
Still appreciative of any additional ideas or thoughts.
Wishing everyone a very Happy 4th of July !!
Yesterday.
-Forced the TPS to read .525 at closed throttle position. Issue remains the same.
Will work on testing the valve train next. Will post any updates.
Still appreciative of any additional ideas or thoughts.
Wishing everyone a very Happy 4th of July !!
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Joined: Aug 2000
Posts: 62
Likes: 2
Hello everyone..
I'm sorry for not updating this thread in a while. I was sidetracked with many other seasonal projects.
Unfortunately I found what multiple people told me it could be and what to look for.
The exhaust valve on the #2 cylinder is inop. Further testing so far suggest that the cam and or lifter is worn down.
Obviously I now have a different project ahead but hopefully it will solve my issue. I might have some questions about what parts to replace and will also update this thread with the final results of the repair.
** Most important I want to thank everyone for taking your time and knowledge to help me get this far. I appreciated it !!
I'm sorry for not updating this thread in a while. I was sidetracked with many other seasonal projects.
Unfortunately I found what multiple people told me it could be and what to look for.
The exhaust valve on the #2 cylinder is inop. Further testing so far suggest that the cam and or lifter is worn down.
Obviously I now have a different project ahead but hopefully it will solve my issue. I might have some questions about what parts to replace and will also update this thread with the final results of the repair.
** Most important I want to thank everyone for taking your time and knowledge to help me get this far. I appreciated it !!
Instructor
Joined: Sep 2014
Posts: 160
Likes: 2
From: Annapolis Maryland
same ole problem?
Good that you found yr exhaust valve problem! Will you have to replace yr cam and lifters? Other than OEM would be interesting to know if there's a better cam that could still be used with the stock EFI setup
Last edited by cloudshe; Aug 10, 2025 at 10:57 AM.
Instructor
Joined: Sep 2014
Posts: 160
Likes: 2
From: Annapolis Maryland
Hey Buccaneer! Thanks much for the update on yr PA trip, sounds like you were able to round up what Bob would have wanted you to have.
Best of luck on your mission, hope to be one of yr first customers!
Cloudshe
Grasonville, MD
Best of luck on your mission, hope to be one of yr first customers!
Cloudshe
Grasonville, MD
Last edited by cloudshe; Aug 11, 2025 at 02:07 PM. Reason: wrong name in text
Safety Car
Joined: Nov 2005
Posts: 3,532
Likes: 1,185
From: Arizona - If you don’t know CFI, STOP proliferating the myths around it...
Hello everyone..
I'm sorry for not updating this thread in a while. I was sidetracked with many other seasonal projects.
Unfortunately I found what multiple people told me it could be and what to look for.
The exhaust valve on the #2 cylinder is inop. Further testing so far suggest that the cam and or lifter is worn down.
Obviously I now have a different project ahead but hopefully it will solve my issue. I might have some questions about what parts to replace and will also update this thread with the final results of the repair.
** Most important I want to thank everyone for taking your time and knowledge to help me get this far. I appreciated it !!
I'm sorry for not updating this thread in a while. I was sidetracked with many other seasonal projects.
Unfortunately I found what multiple people told me it could be and what to look for.
The exhaust valve on the #2 cylinder is inop. Further testing so far suggest that the cam and or lifter is worn down.
Obviously I now have a different project ahead but hopefully it will solve my issue. I might have some questions about what parts to replace and will also update this thread with the final results of the repair.
** Most important I want to thank everyone for taking your time and knowledge to help me get this far. I appreciated it !!
Also, today is the day we start the hack into XP, which IMO should be a relatively easy process. Once we bypass the PW and able to boot to the desktop, we can find the apps used to create everything and the current source code Bob used. This has been a very slow process since we are on their schedule, not mine. I did get a quote from a foundry in OH while there and a was a bit high to my liking. I'm going to have a talk with them this week and see what I can work out. The real problem for me is that there are not many foundries out west vs midwest and east coast. We already tried CA and they sucked and were not doing us any favors. This is the main reason we pulled the tooling from them. Everyone have a great upcoming week.
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Thanks @Buccaneer and @cloudshe for your replies.
If this was a valid test to see if it was just a lifter.? While someone cranked the motor I watched the lifter through the hole in the head and the body did not move at all, I also pushed down on the pushed down on the pushrod and could feel a little bit of movement, the movement could have been up and down but it was so small that it would never have moved the valve. Is there any hope that it still could be just a lifter??
I would definitely appreciate your suggestions regarding what parts to buy and replace.
I would really like to keep everything else stock and also need avoid any risk of loosing reliability on any other components or systems on the car.
Thanks again guys.. Much appreciated!
If this was a valid test to see if it was just a lifter.? While someone cranked the motor I watched the lifter through the hole in the head and the body did not move at all, I also pushed down on the pushed down on the pushrod and could feel a little bit of movement, the movement could have been up and down but it was so small that it would never have moved the valve. Is there any hope that it still could be just a lifter??
I would definitely appreciate your suggestions regarding what parts to buy and replace.
I would really like to keep everything else stock and also need avoid any risk of loosing reliability on any other components or systems on the car.
Thanks again guys.. Much appreciated!
Burning Brakes
Joined: Feb 2020
Posts: 904
Likes: 569
From: Central NJ
I would definitely appreciate your suggestions regarding what parts to buy and replace.
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Instructor
Joined: Sep 2014
Posts: 160
Likes: 2
From: Annapolis Maryland
i suppose as a minimum you'll need a new flat tappet cam and lifters, a gasket kit for the intake man, timing chain cover and crankshaft seal, and a lube kit for the break in plus the usual oil change staples. at least that's all i used when the #1 ex lobe flattened on my '72, my budget at the time. car ran great after that putting about 1000 miles on it plus some autocross time. had to sell it to avoid putting $$$ into it to please the Calif CARB folks when they tightened up on the inspections a while back. never noticed any extra metal or destruction fm the cam wear, they seem to grind down pretty quickly once the hardening is worn thru, not uncommon at least in GM V8's
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I have never seen a lifter go bad like that without damage to the cam as well, plan on both.... Timing gear and chain, sure why not since you are in there, same might be said for the balancer and front oil seal. The bigger issue is how much metal is floating around in that engine from the cam lobe and lifter....Take a close look at the top end/galley and run a strong magnet around to see what it picks up, cut open the oil filter so see how much is in there and since you have to drop the oil pan a little to get the front cover off, take it all the way off and check it for metal sludge.... Depending on how much you find you might end up taking a Few bearing caps off to check the bearings for wear. If you are going to do this then do it right,,
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