Thought the 370cc injectors fouled plugs, but I still have a sputter at 10-12lb boost

[big-phil]

At first I thought while tunning the AFM for the larger injectors, that I fouled my plugs because I just started having a bad sputter the other day at about 4500 rpm or 10-12 pounds boost, so I replaced them, but that was not it. Plugs the pluge read good.

 

Then I smelled gas this morning, and found a leaky injector, I bought 8 so replaced the bad one and thought that was it, no still sputtering.

 

Then I saw that the silicone tube from turbo outlet to I/C plumbing had a bad crack so I replaced it, and thought that was it, no still sputtering.

 

So then I replaced the I/C plumbing from the radiator hoses to 2 1/2" PVC, I thought maby it was ballooning, no still sputtering.

 

Now it was running strong all the way to 15 pounds boost, for a couple days.

I did make a 3 hour drive to pick up a P90 head, then 3 hours home (duh) I don't know if that had anything to do with anything, but when I punch it in any gear it gets to about 4500rpm, or 10-12 pounds boost, It starts sputtering.

 

could it be Timming, I'm going to hook up the fuel pressure guage again to be sure all that checks out.

[Guest bastaad525]

get a can of electric parts cleaner spray, disconnect your wiring harness from your ece and sensors and clean everything off. Allow to dry and put back together.

 

many of us have had this exact same thing happen, after a while the car will start to sputter under boost... and many of us have found it's simply our old wiring harnesses corroding and having bad connections.

 

Often, just unplugging the connectors from your ECU and plugging them back in can clear the problem up but it will usually come back in a very short time. Cleaning them with cleaner spray might buy you a couple weeks or months.

 

Best thing to do after cleaning them is put a healthy coating of dielectric grease on all of the connections to help keep them from coroding again. I used to have to clean off my connections once a month, now I haven't had to clean them in over a year.

 

Try cleaning your connections first before you do anything else.

[big-phil]

OK thanks, I've been trying to do the 3rd gear roll on at 3500rpm for ya, but it don't want to go over 12ish lbs boost.

 

I think I also found an exhaust leak at the manifold on piston #1, I remenber now when putting the turbo manifold on I bent the gasket over on the #1 right under the thermostat housing. So I need to get a new gasket also. Awwwwwwww I don't want to take in apart AGAIN!

[big-phil]

I think I fixed it, I put an Accell super coil in, and leaned out the AFM a little more, and it now pulls good and hard to 15 pounds boost.