Engine One Side Hot, One Side Cold, Runs Like Crap
Race Director
Joined: Feb 2004
Posts: 12,518
Likes: 19
I pulled the FPR and it looked fine and the plunger seemed to work okay, Hard to tell it’s a pretty strong spring. I have another FPR but did not replace it.
I also pulled the fuel rails high enough to see if the injectors are leaking and they are not.
I had my wife turn the key so I could see if the injectors had a spray and the only one that sprayed anything at all was number one cylinder. So what would cause this?
I also pulled the fuel rails high enough to see if the injectors are leaking and they are not.
I had my wife turn the key so I could see if the injectors had a spray and the only one that sprayed anything at all was number one cylinder. So what would cause this?
Instructor
Joined: Aug 2009
Posts: 146
Likes: 0
From: Broadway Virginia
Hmmm...Seems to me that if you pulled the fuel rail to watch the injectors and you turned over/cranked the engine that ALL of the injectors on one side should spray in unison (batch fire). I believe they should all spray together and not sequentially.
If only the number ONE injector sprayed and you confirmed that all the injectors on that side received a signal as confirmed by the noid light......the conclusion would be three bad/plugged injectors on that particular rail.
What about the other side/rail?? How many on the other side sprayed? Did you check both sides or just one? it is not clear.
If only the number ONE injector sprayed and you confirmed that all the injectors on that side received a signal as confirmed by the noid light......the conclusion would be three bad/plugged injectors on that particular rail.
What about the other side/rail?? How many on the other side sprayed? Did you check both sides or just one? it is not clear.
Thread Starter
Pro
Joined: Nov 2009
Posts: 583
Likes: 0
From: Maple Grove Minnesota
Pulled the injectors off the rails today and it looks like I’ll need new ones? The inlets look like they have a lot of dirt in them and also found dirt in the rails.
Where is a good spot to put a second inline filter, I’m guessing at the tank?
Where is a good spot to put a second inline filter, I’m guessing at the tank?
Instructor
Joined: Aug 2009
Posts: 146
Likes: 0
From: Broadway Virginia
I think the thing to do would be to replace or send the current injectors out to be cleaned, if possible. For my money I would replace them, BUT ONLY IF I could sufficiently clean the dirt out of the system first. No need to ruin great performing costly injectors with more of the same crud.
Remove and Flush out the rails, and supply line too somehow.
Replace the stock fuel filter, inspect it for crud.
Check the sock on the in tank fuel pump for crud.
Think about dropping the tank and flushing it depending on what you find in the sock filter/tank.
It is likely that you have been getting bits of crud in the sealing surfaces of the FPR not allowing it to close off properly.
Can you identify the origin of what you found? Is it rust, dirt, metal shavings,.....??
I would not install a second filter just yet, just replace and regularly check and replace the factory one again.
Remove and Flush out the rails, and supply line too somehow.
Replace the stock fuel filter, inspect it for crud.
Check the sock on the in tank fuel pump for crud.
Think about dropping the tank and flushing it depending on what you find in the sock filter/tank.
It is likely that you have been getting bits of crud in the sealing surfaces of the FPR not allowing it to close off properly.
Can you identify the origin of what you found? Is it rust, dirt, metal shavings,.....??
I would not install a second filter just yet, just replace and regularly check and replace the factory one again.
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Thread Starter
Pro
Joined: Nov 2009
Posts: 583
Likes: 0
From: Maple Grove Minnesota
I just replaced the sock and pump last week while having the current problem. I didn’t inspect the old one when I removed it.
There must be a little water in the tank the metal inlets on the injectors have a little rust on them.
Probably have to remove the tank and get it cleaned.
The injectors and rails appear to have dirt bits in them
There must be a little water in the tank the metal inlets on the injectors have a little rust on them.
Probably have to remove the tank and get it cleaned.
The injectors and rails appear to have dirt bits in them
Instructor
Joined: Aug 2009
Posts: 146
Likes: 0
From: Broadway Virginia
Condensation most likely. I recall you said the PO replaced the injectors. I wonder if they are NOT stainless steel, thus alcohol (water) intolerant. When I replaced mine (1988), I found no rust on them but was told that they were steel (factory originals) and would not handle the ethanol in use today. The ethanol (10%) tends to be a wee bit corrosive and attracts water which is not good for the internals of steel injectors. Most if not all new injectors are stainless.
If there had been alot of trash on the sock filter when you removed it you would have noticed it.
What about the fuel filter? Did you,...are you going to change it?
If there had been alot of trash on the sock filter when you removed it you would have noticed it.
What about the fuel filter? Did you,...are you going to change it?
Instructor
Joined: Aug 2009
Posts: 146
Likes: 0
From: Broadway Virginia
The problem may then just be isolated with the injectors. It wouldn't be a bad idea to replace the fuel filter again once this is all worked out and you have had a chance to run a half dozen tanks of gas thru the system.
Did you notice any unusual amount of debris in the old filter?
Did you notice any unusual amount of debris in the old filter?
Burning Brakes
Joined: Oct 2009
Posts: 773
Likes: 2
From: Minneapolis MN
Dropping the tank is alot of work.Add some HEET to your gas tank.This will attract the water & burn it.My opinion is flush out fuel rail & lines,replace fuel filter again,talk to FIC about injectors-rebuild or replace,siphon as much gas out of fuel tank as possible,put everything back together add HEET & refill with a quality gas as well as premium.After you go through one full tank add one full bottle of Techron Fuel injector cleaner(the best in my opinion) & buy one bottle of Seafoam & add a half bottle of Seafoam to engine oil.Drive car for about 30 mins then change oil & filter.This works great at removing sludge from an engine.Be careful & don't drive the car at WOT when the Seafoam is in the engine oil.Keep us updated keith
, except that if the PO installed rebuilt older steel body injectors I would definitely replace them with newer stainless ones to avoid water/alcohol problems in the future.
Thread Starter
Pro
Joined: Nov 2009
Posts: 583
Likes: 0
From: Maple Grove Minnesota
I replaced the filter yesterday for the second time. Bought Bosch III’s from Jon at FIC, cleaned the rails installed the injectors and ran a little fuel from the line.
I’m not sure about the injectors as they do not use clips to hold them into the rails they just kinda float between the rail and intake not really seated firmly to either.
Using the still new (old) FPR I hooked up the pressure gage and turned the key and had no leaks around the injectors. The pressure did drop to 32 after 5 minutes but seemed to be holding.
Tomorrow I’ll put the plenum back on and get everything hooked up again and see what happens.
I’m not sure about the injectors as they do not use clips to hold them into the rails they just kinda float between the rail and intake not really seated firmly to either.
Using the still new (old) FPR I hooked up the pressure gage and turned the key and had no leaks around the injectors. The pressure did drop to 32 after 5 minutes but seemed to be holding.
Tomorrow I’ll put the plenum back on and get everything hooked up again and see what happens.
Thread Starter
Pro
Joined: Nov 2009
Posts: 583
Likes: 0
From: Maple Grove Minnesota
Got everything back together and turned the key and lost fuel pressure again, Took the plenum off again and replaced the FPR put it back together and lost pressure again. WTF? 
I’m not getting enough fuel to the injectors it’s all going down the return line as soon as the pump comes on. If I pinch off the return line it will start and run half way descent.
I’m not getting enough fuel to the injectors it’s all going down the return line as soon as the pump comes on. If I pinch off the return line it will start and run half way descent.
Instructor
Joined: Aug 2009
Posts: 146
Likes: 0
From: Broadway Virginia
When you say it lost pressure both times, did it go to zero or to what?
Double check the spring in the FPR. And check to see if you have the correct FPR. Double check the part number.
The spring pressure should not be that easily overcome by the pressure from the pump.
I do not recall.....did you or the PO replace the pump? It isn't a high volume/high performance pump is it? Just asking?
Is it even possible to have the lines switched somehow?? I am not sure that it would cause this.
______
Edit: Reread all previous posts, you replaced pump, had the problem before and after.
What could possibly cause the FPR to bleed off that much pressure?? Anybody??
Last edited by walter schweigert; Jul 10, 2010 at 11:01 PM.
Burning Brakes
Joined: Oct 2009
Posts: 773
Likes: 2
From: Minneapolis MN
Maybe you need a adjustable fuel pressure regulator?Possible you got wrong part(correct part number but boxed wrong?).Maybe there is a restriction in fuel rail?Did you clean fuel rail before installing fuel injectors to make sure its clear?Is it possible to hook up fuel lines backward at fuel rail?Is it possible the previous owner installed a different year fuel rail?Hang in there keith you made it this far don't give up-I mean look,you fixed it so it starts/turns over,fixed most of the wiring,& fixed it so you have injector pulse
Thread Starter
Pro
Joined: Nov 2009
Posts: 583
Likes: 0
From: Maple Grove Minnesota
Not sure what I did or didn’t do but the car is running fine again. I took it for about a ten mile drive on the freeway and city streets with no issues.
I’m beginning to think this car has a mind of its own or it possessed.
I’m beginning to think this car has a mind of its own or it possessed.