I'm all ears!!!!! Can you explain? And also tell me if I'm correct about it wold be running like s**t if it were a dead cyl or a valve. I just want to note that I am not questioning anyone who has put input in. I just know the basics and I'm trying to learn as much as I can. If I'm wrong please tell me. I am all ears to everyone!!!!!!!!!!!!!

 

I also forgot tuner said that when he replaced my plugs before the tune he put that little camera down inside the cyl and he said that they looked good and no signs of detnation. I guess if this is true this is a good sign....

 

Run a pressure test... looks like a major leak to me. Either that or your injectors are done.

 

well, there are a few things that could leak. Manifold to head, manifold to turbo flange, turbo to downpipe.

If any of those weren't tightened properly or had a bad gasket then you would have a leak.

Now that i've mentioned it it sounds like the most likely candidate. The car would still run yet the wideband would be crazy. It's just a wideband reading and not an actual representation of what's going on in the cylinders.

also, 6psi at 2500rpm does sound normal now that i know you have a greddy 18g.

You can start the engine and let it idle then using some type of smoke machine (anything that can produce a small stream of smoke) direct it up and move it around the manifold and all the connections. If there is exhaust pulsing out of one of the connections you will see the smoke being pushed away.

also, he can use a long piece of hose and move it around the areas to hear it hissing. The car only needs to be idling so it's pretty simple to do.

 

Leak? Like what are you thinking as far as a leak? We boost leak tested everything and I was good. As far as a upstream exhaust like Binder said, that makes sense, but how would you go about looking for it being it's so tight in the engine bay? Injectors bad.... I'm hoping!!!!

 

i doubt the injectors. do you know the probability of having 3 injectors from a batch all bad and you managed to put them all in 1 bank? Probably a better chance at the lottery.

He probably means exhaust leak. Boost leak (as from your boost tests) is for the cold side where boost is produced. The boost side can be perfectly sealed with no leaks and still have a nasty exhaust leak which causes air to get into the system and screw with the o2 sensor.

Exhaust leak would be the cheapest and easiest problem in this situation. Either a retorque of the studs or a new gasket. Pretty cheap.

 

Ok thanks for getting back!!! I'll will relay the info. Also you were saying the car will still run just the the wideband would be going crazy. Are you saying if theres a leak? I have been reading on another thread about a guy who had a lean spot at 2400rpm. Others were sayin they had a issue to and the car would pop andkinda fall on it's face for a second. If it were true would my car do somewhat the same if it were really at 18 a/f at 2500rmp?
And just say there were a dead cyl or a valve issue, wouldn't the car run like crap?
I just want to thank everyone for helping out!!!!!!! I'm not as knowledged as alot of you and it's the reason why I ask on here and I want to thank you all once again!!!!!

 

I'm hoping it's somthing simple!!!!! Like I said I'm hoping it's nothing internal!!!

 

if there was engine damage or 18:1 a/f the car would run like crap and i would also be safe to say there is a huge probability that the engine would be severely damaged with 18:1 a/f and 6psi of boost.

 

Binder: Now that I'm thinking the whole thing out I said the same thing about the injectors. What are the chances of the 3 injectors going bad. And I said this yest. to the tuner his response was thay it only needs to be 1. I don't know. The leak makes more sense tho. Basically it's un metered air escaping correct? In turn would look lean and explain why the car still runs ok when it looks as lean as it's showing.

 

So your saying if the car is runing ok then there prob. isn't any internal damage?

 

it means it's probably not a true 18:1 a/f. Just in light vac driving when i had a dead spot and it hit 18:1 the car would literally fall on its face and stall out. At 6psi the response would be even worse if it was actually 18:1 a/f in those cylinders.

An exhaust leak has nothing to do with "metered" air. It's just an exhaust leak letting air in which is 20% oxygen. That will make the a/f go crazy high.

 

Gotcha ok thanks buddy. Well I'm going to keep up on this thread and note everything thats going on to the end in hopes that it will help somebody else in the long run.....
A buddy of mine I just talked to that big into turbo car said I could be a spark issue. I duno.
Really wish I knew more about this. I got into this very quick and haven't had experience with built turbo cars.....

 

spark on only 3 cylinders?

each cylinder has its own coil pack and if one wasn't firing you would get a misfire, misfires cause rich conditions because the unburned fuel would run right out of the exhaust ports into the exhaust.

not a spark issue

 

why not just swap your gauge to both sides of the exhaust and see if the AFR stays the same or goes to 18:1.

these are all very basic tests that your shop should not need internet mechanics to suggest...

 

I could do all this the problem is, is that it's at a shop and dude wants to charge everytime the intake is takin off/on. I think I'm goin to tell him to do the simple things first. Also it's a dyna pak dyno so hooking it up to the dyno is a pain in the ***. I'm guessing this would have to be done to hook his sensor up to the other side.

 

OK then, my bet is on a bad injector.

 

sounds like you should take the car home and sort the problem out yourself and then take it back when its running properly.

Throw in stock injectors and stock ecu, stay outta boost and get it out of the shop.

Out of every single suspected bad injector theory, there hasnt been 1 that has come back bad. Thats not your problem. Simple spark plug evaluation will tell you that for free.

 

This is good advice.

I have to trouble shoot my system as well. I am having to add fuel to one bank at a certain RPM range (under load), take it out of the other bank and then further in the RPM's do the same but in opposite banks. Kind of strange, and all this since header and larger injector install.

 

Ok well so far did the compression test and bank 1 is from 132 to 140. Bank 2 is from 140 to 149. The tech. said bank one looks goos and bank2 has alot of carbon build up which is most likely from insufficient firing which would cause higher compression. Fuel line all seemed to be clear, so it's pointing in the injector direction. We'll see ( hope so!! )