The Woes of a 6 Bolt Swap

[XiKeiyaZI]

There are dozens upon dozens of threads out there about similar issues, some of which relate and others which are just ridiculous. Most, however, are not resolved and leave me questioning what the heck is going on. So let's just move on into this issue and see if we can figure something out.

A : All mods in my profile are up to date.

B (The Issue) : The car struggles to idle. At first I figured it was running rich as it eventually fouled out my plugs and left them drenched in fuel. After pulling the codes with EvoScan I found that my CTS was bad so I replaced it. Slapped in a fresh set of plugs and went onwards. With the wideband active, starting the car it idles up around 2000rpms and about 10.8AFRs. I know that cold start is supposed to be a bit rich. Idle doesn't drop but as the car warms up the AFRs will eventually reach up around 13.8ish. After that the RPMs will randomly drop down from 1800ish to 400, struggle, jump back up, and then eventually die. AFRs stay around the same level.

C : I have had someone much more familiar with ECUflash set my injectors (550's) as well as ensure the deadtimes are proper (160ms) and it helps to keep the car running a bit longer. After a few times running, though, the car will foul the plugs and I will either need to clean or replace them to get it running again. There are no further DTC's to go off of.

D : I have replaced the PTU with a known working one. Installed working stock coils and good wires. Checked for loose hoses. Set the fuel pressure to 43psi. I have even checked my mechanical timing a total of 4 times and each time it is dead on - I'm paranoid about timing after all. Throttle body is adjusted 100% properly. I'm at a loss. The only thing I can think of is either a bad MAF or there are adjustments in the ecuflash tune which need to be made at this point.

Any insight?

 

[colbyc]

Well I can tell you its not the settings in ecuflash that need to be adjusted. You are close to stock so it should atleast idle without changing much but the injector latency and scaling. I would check the MAF out, have you tested your ISC?

 

[XiKeiyaZI]

I was honestly thinking about heading out and doing that first thing in the morning.

 

[dsmcurse]

Im gonna have to say if you dont have any vacume leaks and you have idle surge like that its from having a tad to much advance at your base timing and having the BISS unscrewed to much at the same time. On your data logger it should say ISC (idel speed controll) this number should bounce arond between 30 and 40. I bet your says like 80

 

[XiKeiyaZI]

See, I'd absolutely love to know what my datalogger says but Evoscan just isn't working. I've tried 2.7 and 2.9 and made sure that the FTDIxx.dll (or whatever it's called) is downloaded and installed in my system32 folder. All it does is freeze the program. The only access I have so far is to check DTCs.

 

[XiKeiyaZI]

Ripped out the ISC - it tested perfect. -_-;

 

[bryanwheat]

What cam sensor are you running?

 

[XiKeiyaZI]

Using a Greentop. Think it could potentially be a bad CAS?

 

[95talongirl]

Have you checked to make sure the throttle body shaft seals are not leaking? That might not be all of the problem, but it could effect the idleing.

 

[XiKeiyaZI]

I've doused everything in ethanol at least a dozen times and not once have I heard the idle spike.

 

[XiKeiyaZI]

I got creative with a fogger system that I had and set it up to route through a hose on my intake pipe. Blocked off in inlet and fired it up.

With the low pressure smoke, I found a major leak at my catch can. Fixed that - Faulty fitting. Also found a split cap on the intake pipe. Also found a leak at the coupler from the intake pipe to the turbo inlet. Finally I found a leak at the J-Pipe flange. That one might be difficult to correct. At the Intake manifold, I found nothing. Had the throttle closed and all hoses capped - Also set the crank to 4*btdc to ensure the valves were closed. So, I believe after correcting the leaks in my intake system I should be okay.

 

[ThunderChild]

fix the vacuum leaks. then, id check your ignition system. test your coils, wires and what kind of plugs are you using?

it sounds like you are getting weak spark and after the several minutes of running they are getting soaked. the only other thing i could think that would cause this is injectors just pissing fuel in, but your afr's start to look better the longer it runs. then the plugs foul.

test the coil for resistance, and test your wires. (just cause they may be new, doesnt mean theyre good) i believe around 10k ohms per foot is the max youll want. im unsure on coil specs.

hopefully you find something, good luck!

 

[XiKeiyaZI]

Using good 7mm wires. Going to change the plugs yet again - BPR6ES NGK. Coil is good - pulled from a perfectly good running vehicle. Even switched back to the stock FPR just in case.

Now, I fixed the leaks and know that I have a couple more -somewhere- that I can't pinpoint. I got the idle down to 1000rpm without burying the BISS. Set the base timing also, finally. She runs smoother but still has a very obvious series of misses. AFRs stay between 14.3 and 15.1 as opposed to 13.8 to 16.4 due to leaning out and dumping fuel.

Fairly sure my BOV is leaking internally around the relief seal. I also think I have an intake manifold gasket leak but I can't confirm it. I've tried pressuring the intake system while setting the intake cam to 30* BDC, using a smoke machine, and also spraying around with carb cleaner and Propane. Nothing. God forbid it's a throttle body seal. I went through 3 on my last car, each one "rebuilt" and every one of them still leaked. $100+ to replace a seal is just silly to me, but I never have good luck with removing the damn throttle plate screws. Also my Vacuum is hovering around 12psi at idle. I know I should lose a little vacuum due to the cams, but that's just...ridiculously low.

Running out of ideas, though.

 

[XiKeiyaZI]

After quite a bit of research I found the information about the 10-15 vacuum level at idle. Happy to say that I found that. I was a bit worried.

I did some more messing around and I just couldn't believe that I had a boost leak -that- big. I ripped off the throttle body elbow, pulled the ISC plug, and checked the screw for my throttle plate. Apparently while I set the TPS perfectly, it was off due to the throttle plate stop screw - it was in a full 10 turns for some reason. So I backed it out so as it wasn't touching the plate, then screwed it in a full 1 1/4 turn, reset the TPS, turned the BISS in completely and then back out 2 turns - after 10 minutes of idling it lined out, AFRs stayed stable at 14.4-14.7, and she dropped to 850-1000rpm.

Now I discovered a coolant leak from the Heater Core hose