82 CE Acceleration Problem - HELP!
Thread Starter
Heel & Toe
Joined: Jul 2006
Posts: 22
Likes: 0
From: CO
82 CE Acceleration Problem - HELP!
Hey all,
I've searched the forum for some answers, but haven't found the final answer yet.
My 82 cross-fire runs fine at idle and when revving the engine without any load (i.e. in neutral). However, when it's in drive it has trouble accelerating--it lurches forward when pumping the gas, then will surge ahead when it gets to about 30 mph. If I back off of the pedal, I can get some power, but not a lot.
The timing seems fine--the total timing is 36-37 deg. I'm still figuring out how to get the vaccum advance timing numbers from all the previous, well-known posts--I'm still learning this part.
Is this a vacuum issue or something else?
I've searched the forum for some answers, but haven't found the final answer yet.
My 82 cross-fire runs fine at idle and when revving the engine without any load (i.e. in neutral). However, when it's in drive it has trouble accelerating--it lurches forward when pumping the gas, then will surge ahead when it gets to about 30 mph. If I back off of the pedal, I can get some power, but not a lot.
The timing seems fine--the total timing is 36-37 deg. I'm still figuring out how to get the vaccum advance timing numbers from all the previous, well-known posts--I'm still learning this part.
Is this a vacuum issue or something else?
Melting Slicks
Joined: Jul 2005
Posts: 2,740
Likes: 3
From: Aurora Ontario
Or the EGR. Push up on the diaphram. Should move easily. Should notice a difference in idle when pushed.
Jim
Thread Starter
Heel & Toe
Joined: Jul 2006
Posts: 22
Likes: 0
From: CO
I bought it in the fall of 2004 and have not done anything to it besides routine maintenance. I'll check to see how difficult checking the fuel filter will be and take a look at the EGR, etc., and I'll let you know.
Thanks for the suggestions!
Thanks for the suggestions!
Instructor
Joined: Aug 2006
Posts: 104
Likes: 0
From: Apache Junction Arizona
I had these problems with my 82 and I changed out the stock fuel pump with an 85-87 pump and had the throttle shafts bushed. No more problems with the motor acting like it is running out of gas and/or have a bad vacuum leak. If you haven't already, check out the Crossfire Injection Vault: http://www.crossfire.homeip.net/cftest/ It's all about CFI there!
Also check out DCS: http://crossfireinjection.net/
this is where I got everything I needed to get my CFI running better than it probably did new.
Good Luck!!
Also check out DCS: http://crossfireinjection.net/
this is where I got everything I needed to get my CFI running better than it probably did new.
Good Luck!!
Burning Brakes
Joined: Nov 2005
Posts: 924
Likes: 15
From: DFW Metroplex Texas
If you are not seeing any codes (CE light coming on) Im still thinking its a fuel delivery issue.
Send tracdogg2 (Mike) a PM if you have any specific questions. He is a expert when it comes to C3s. Mike would probably be happy to give some ideas.
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...
Hi JK, here is what I would do.
1. Check your FP since that is really important on a CF, set it to 14psi. Anything less is NOT going to cut it on a CF no matter what the GM manual says.
2. Check those TB shafts for a leak by trying to move them. If they move at all, they are worn and bad...PERIOD! Phill suggested a site that has a guide on how to check that in the How-To section, use it.
3. Your total timing "may" be a tad high. Base is 6* with EST pulled, but you can set it as much as 10* if it doesn't ping. This is probably not your issue though.
4. TPS set to .525v
5. IACs...ensure they are moving and not sticking.
6. EGR...diaphram movement as suggested.
7. CTS...replace with the newer two pin weather pack type which are more reliable.
These are the main items on a CFI motor that cause the majority of the issues many members see with their cars. The TB balance is important as well, but you have other issues going on before you get to that. This is only my opinion, others will vary. My feeling is that you are running lean and out of fuel...check that FP. Hope you get her running right soon.
Post your results for others.
1. Check your FP since that is really important on a CF, set it to 14psi. Anything less is NOT going to cut it on a CF no matter what the GM manual says.
2. Check those TB shafts for a leak by trying to move them. If they move at all, they are worn and bad...PERIOD! Phill suggested a site that has a guide on how to check that in the How-To section, use it.
3. Your total timing "may" be a tad high. Base is 6* with EST pulled, but you can set it as much as 10* if it doesn't ping. This is probably not your issue though.
4. TPS set to .525v
5. IACs...ensure they are moving and not sticking.
6. EGR...diaphram movement as suggested.
7. CTS...replace with the newer two pin weather pack type which are more reliable.
These are the main items on a CFI motor that cause the majority of the issues many members see with their cars. The TB balance is important as well, but you have other issues going on before you get to that. This is only my opinion, others will vary. My feeling is that you are running lean and out of fuel...check that FP. Hope you get her running right soon.
Post your results for others.
Last edited by Buccaneer; Jun 22, 2007 at 12:46 PM.
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Thread Starter
Heel & Toe
Joined: Jul 2006
Posts: 22
Likes: 0
From: CO
All good stuff guys.
Checked the EGR tonight--that's not it--there's clearly a RPM change when I push up on it.
Yes, the Check Engine light has come on before, but only a couple times. I'm gonna check the codes tomorrow as recommended in the shop manual.
Guess I'll look at changin out the fuel filter and possibly the pump next.
Buccaneer, you have some great suggestions, but unfortunately I'm not that well-versed in your acronyms--still learning the lingo. If you don't mind, please clarify them for me. Thanks!
I'll check the other websites too. I'm trying to fix her when I'm not helping out with the new kid in the house, so please be patient and keep the comments comin'!
Checked the EGR tonight--that's not it--there's clearly a RPM change when I push up on it.
Yes, the Check Engine light has come on before, but only a couple times. I'm gonna check the codes tomorrow as recommended in the shop manual.
Guess I'll look at changin out the fuel filter and possibly the pump next.
Buccaneer, you have some great suggestions, but unfortunately I'm not that well-versed in your acronyms--still learning the lingo. If you don't mind, please clarify them for me. Thanks!
I'll check the other websites too. I'm trying to fix her when I'm not helping out with the new kid in the house, so please be patient and keep the comments comin'!
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...
Buccaneer, you have some great suggestions, but unfortunately I'm not that well-versed in your acronyms--still learning the lingo. If you don't mind, please clarify them for me. Thanks!
FP=fuel pressure
CF=crossfire
CFI=crossfire injection
GM=Hmmmm...Duh
TB=throttle body
EST=electronic spark timing
*=degrees
TPS=throttle position sensor (on rear TB)
IAC=idle air control (both TBs)
EGR=exhaust gas recirculation
CTS=coolant temperature sensor
mv=millivolts 525mv=.525v or just over a .5v
v=volts
Last edited by Buccaneer; Jun 22, 2007 at 12:47 PM.
Thread Starter
Heel & Toe
Joined: Jul 2006
Posts: 22
Likes: 0
From: CO
Well,
I changed out the O2 sensor tonight. A little better but doesn't totally fix the issue. She still hesitates from the start and surges until 40 mph or so.
Waiting for a fuel filter to arrive Monday.
Can't find a fuel pressure gage (gauge?) anywhere. The ones on eBay don't work for TBI. Any ideas?
I'll check the stuff Buccaneer recommended tomorrow as best I can.
That's all for now.
I changed out the O2 sensor tonight. A little better but doesn't totally fix the issue. She still hesitates from the start and surges until 40 mph or so.
Waiting for a fuel filter to arrive Monday.
Can't find a fuel pressure gage (gauge?) anywhere. The ones on eBay don't work for TBI. Any ideas?
I'll check the stuff Buccaneer recommended tomorrow as best I can.
That's all for now.
Thread Starter
Heel & Toe
Joined: Jul 2006
Posts: 22
Likes: 0
From: CO
OK, so it took me some time to work on it, but I think I`m getting closer.
I replaced the fuel filter and she`s driving a little better, but not perfect. After I checked the TBs for movement, I found that there is slight movement on the rod between the two TBs from side-to-side and up and down. So this points to a vacuum leak from what folks have been writing.
My next questions are: Will driving it as it is do any damage to the engine? If I`m trying to keep the engine all stock, is it important to keep the TBs the same? (I know that I can send them in to get bushed, but it sounds like they'll send back two different TBs once mine arrive at their shop in order to cut down on time.)
Any other ideas?
Thanks for your help!
Jason
I replaced the fuel filter and she`s driving a little better, but not perfect. After I checked the TBs for movement, I found that there is slight movement on the rod between the two TBs from side-to-side and up and down. So this points to a vacuum leak from what folks have been writing.
My next questions are: Will driving it as it is do any damage to the engine? If I`m trying to keep the engine all stock, is it important to keep the TBs the same? (I know that I can send them in to get bushed, but it sounds like they'll send back two different TBs once mine arrive at their shop in order to cut down on time.)
Any other ideas?
Thanks for your help!
Jason
Instructor
Joined: Aug 2006
Posts: 104
Likes: 0
From: Apache Junction Arizona
You should be able to drive it okay without any worries. If you get any movement in your TB's; time to get them bushed! I had mine done at CrossfireInjection.net (DCS) and they just exchanged the bases which the throttle shafts run through. These bases are NOT date coded to your year so an exchange wouldn't be a big deal. Like you, I want to keep it stock/original as much as possible and go through great pains to do so.
As for a fuel pressure gauge, DCS sells a fuel pressure assembly which I also have installed - this is not stock but you can remove it once your pressure is set and TB's are balanced. Have you replaced the stock fuel pump yet with an 85-87 pump? This alone made a world of difference for my 82 along with the TB bushings and balancing.
If it's important to you, I'm sure DCS can bush your original TB's but you will never know the difference.
Good luck - your almost there!
As for a fuel pressure gauge, DCS sells a fuel pressure assembly which I also have installed - this is not stock but you can remove it once your pressure is set and TB's are balanced. Have you replaced the stock fuel pump yet with an 85-87 pump? This alone made a world of difference for my 82 along with the TB bushings and balancing.
If it's important to you, I'm sure DCS can bush your original TB's but you will never know the difference.
Good luck - your almost there!
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...
DCS will return your exact TBs if you request that you want those perticular ones back. Some people want the TBs back ASAP so thats why you would get a good core back instead. Most TBs sent in are the same one's sent out. Bushing time is usually only one or two days plus shipping. Hope this helps.
