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I'm not looking at right now, but I believe that they are Bosh. You tear yours down every 3 years just for cleaning ??? I've been looking at what it is going to take to get them out, and it looks like quite a job....
I guess I'll go ahead and jump on it. Any tips or warnings that I need to know about ????
I'm not looking at right now, but I believe that they are Bosh. You tear yours down every 3 years just for cleaning ??? I've been looking at what it is going to take to get them out, and it looks like quite a job....
I have a Holley Stealth Ram so it is easy to do. I do this for my ATVs, Jetskis other cars and diesel vehicles. I did get 1.5 mpg improvements on the diesel car after 100k.
I guess I'll go ahead and jump on it. Any tips or warnings that I need to know about ????
I'm going to crow-bar my way into this thread, this might be helpful to the OP too.
Had one L98 that had a water in the tank problem. That was all cleared up and the car ran like a bear. Until the injectors got heat-soaked and then 3 and 5 although still working were not delivering fuel. Original Bosch-type injectors. I think pintles were corroded and sticking when hot.
Had one with new fuel injectors. 3,5 and 6 same deal although working not delivering fuel at all or not enough fuel. These were Bosch III. Defective injectors.
Went through all the basic stuff first. Suspicious of vacuum leak around the 3,5 and 7 area because of PVC, cold start injector and booster connection on plenum over that area. All good.
Anyway putting in known good injectors from reputable supplier fixed the problem. Really odd that more or less the same injectors were bad.
I'm going to crow-bar my way into this thread, this might be helpful to the OP too.
Had one L98 that had a water in the tank problem. That was all cleared up and the car ran like a bear. Until the injectors got heat-soaked and then 3 and 5 although still working were not delivering fuel. Original Bosch-type injectors. I think pintles were corroded and sticking when hot.
Had one with new fuel injectors. 3,5 and 6 same deal although working not delivering fuel at all or not enough fuel. These were Bosch III. Defective injectors.
Went through all the basic stuff first. Suspicious of vacuum leak around the 3,5 and 7 area because of PVC, cold start injector and booster connection on plenum over that area. All good.
Anyway putting in known good injectors from reputable supplier fixed the problem. Really odd that more or less the same injectors were bad.
OK, I guess coincidences do happen. I was trying to not tear down something that could just be a quick fix, thanks
I'm not looking at right now, but I believe that they are Bosh. You tear yours down every 3 years just for cleaning ??? I've been looking at what it is going to take to get them out, and it looks like quite a job....
It doesn't look like it's too bad-something you'd want to spend a Saturday doing for sure, but for every 3 years that's not bad. I spend a Saturday just CLEANING my car every month or two usually.
It doesn't look like it's too bad-something you'd want to spend a Saturday doing for sure, but for every 3 years that's not bad. I spend a Saturday just CLEANING my car every month or two usually.
Here is the deal. IF you are driving the car daily, fresh fluid comes in and keeps things moving. When you have a C4, you don't drive it daily especially in the winter so fuel sits in the rails. I don't drive my Jetski in the winter not would I. ATV? See above. So the fuel sits in the rail and could form varnish. My diesel car at 100K did show much improvement with cleaning. At 200K, new nozzles were the only answer.
Think about this. When you leave a puddle of water over a couple days and it dries out, you see a white stain. If you do it again and again, won't the stain get bigger?
Here is the deal. IF you are driving the car daily, fresh fluid comes in and keeps things moving. When you have a C4, you don't drive it daily especially in the winter so fuel sits in the rails. I don't drive my Jetski in the winter not would I. ATV? See above. So the fuel sits in the rail and could form varnish. My diesel car at 100K did show much improvement with cleaning. At 200K, new nozzles were the only answer.
Think about this. When you leave a puddle of water over a couple days and it dries out, you see a white stain. If you do it again and again, won't the stain get bigger?
OK, I'm convinced, I'll get on it. Will John Banner know the correct injectors for my car. I saw the link on a previous page. Thanks for your time and help
OK, I'm convinced, I'll get on it. Will John Banner know the correct injectors for my car. I saw the link on a previous page. Thanks for your time and help
These are from cylinders three and five. Notice how five is considerably darker than three.
So, I got to do a compression test today. I haven't done the passenger side yet, but the driver side is even at 90 psi. I know that is under factory spec, but I think that the compression is good. It jumps right up, and the gauge I am using has complaints of showing way lower than the actual compression It's a cheap gauge. Also, it cranks evenly, there isn't a spot where it sounds like a bad compression cylinder.
I also checked the fuel pressure, 40 psi. It doesn't drop when I read the engine. I think fuel pressure isn't the problem.
I also checked the resistance of each of the injectors. It looks like it is about 16.5 projector. It was even across-the-board, so I think that there is not a short. Are used a screwdriver to listen to the injectors, and I could hear them tapping. I think that they are all working. After I finish the compression test, I think I am going to take the injectors out. I might try to clean them, or just replace them.
interestingly, plugs five and seven look black. They were black on the old plugs, too. I just replace these about a week ago, and they are already black. I will attach a photo of those plugs. Again, compression was the same on those two cylinders as the rest of the driver side.
One more thing. There is a hose coming from the bottom of the throttlebody under the Plenum and over to the passenger side. It ends like this. I think that it is supposed to be connected here.
The screws are probably keeping it from leaking at least
One more thing. There is a hose coming from the bottom of the throttlebody under the Plenum and over to the passenger side. It ends like this. I think that it is supposed to be connected here.The screws are probably keeping it from leaking at least
One of those ports goes to the FPR as it is there. The other goes over to the drivers side and plugs into a oneway valve that goes to the HVAC in one direction and down to the vapor canister the other direction. Having problems with controlling the HVAC? The port under the throttle body goes to the EGR switch located on a bracket on one of the thermostat housing bolts. I wouldn't worry about that too much right now, you can get the engine running OK without them being hooked up right.
Edit: meant to say the vacuum line goes down to the vapor canister *area*.. There's a vacuum reservoir down there as well. Wouldn't worry about it just now though.
Last edited by Tod Stiles; Mar 24, 2017 at 07:02 PM.
I'm certain they are even but if all are low, I would rebuild.
Got a new tester gauge and confirmed all cylinders are at 150 PSI - so NO COMPRESSION ISSUES!!!
The 3 cylinders that didn't make much difference when I pulled the injector are pretty fouled up on the spark plugs. My current theory is that the injectors in those cylinders are leaking.
Got a new tester gauge and confirmed all cylinders are at 150 PSI - so NO COMPRESSION ISSUES!!!
The 3 cylinders that didn't make much difference when I pulled the injector are pretty fouled up on the spark plugs. My current theory is that the injectors in those cylinders are leaking.
Great! Saw the pic of the plugs, that's what I've seen on cars with funky injectors. I guess the thing that would give me pause now is it looks as though someone already had the intake off. There are hex head bolts there instead of torx. But what are you gonna do, it's going come off anyway.
I think you've inherited someone else attempt to fix the problem(s) and you have to undo/replace/fix or otherwise deal with what they did. So far seems like you are progressing in that direction.
Don't forget a fuel filter if you do end up replacing the injectors. Keep going, you'll get there!
Great! Saw the pic of the plugs, that's what I've seen on cars with funky injectors. I guess the thing that would give me pause now is it looks as though someone already had the intake off. There are hex head bolts there instead of torx. But what are you gonna do, it's going come off anyway.
I think you've inherited someone else attempt to fix the problem(s) and you have to undo/replace/fix or otherwise deal with what they did. So far seems like you are progressing in that direction.
Don't forget a fuel filter if you do end up replacing the injectors. Keep going, you'll get there!
Already replaced the fuel filter
I know the injectors were replaced about 5 years ago but they've had bad gas sit in them since then.
You're not wrong-there's a lot of little problems with this car. I expect it will take a long time to fix them all. For now, I'd be happy with getting this misfire taken care of.
Got a new tester gauge and confirmed all cylinders are at 150 PSI - so NO COMPRESSION ISSUES!!!
The 3 cylinders that didn't make much difference when I pulled the injector are pretty fouled up on the spark plugs. My current theory is that the injectors in those cylinders are leaking.
OK. You dodged the bullet on the rebuild. Give FIC a call
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