hey whats up guys. i got an issue going on and im starting to run out of ideas. while driving, the car will begin to bog and the AFRs will start going pig rich down to low 11s. it first happened one night while driving home, was doin about 70mph then all of a sudden it started to bog and i had to clutch kick the car back on to get into a parking lot. with taking breaks, it got me home. so the next day i began work to see whats up. the car wouldnt hold idle until after a few tries, then i heard a pretty nasty vacuum leak which lead me to fixing it. here's what ive done in so far:

-i fixed a vacuum hose that had popped off from the LIM that connects to the block beneath my 2nd fuel rail.
-re-calibrated the TPS to make up for the change in idle since fixing the vacuum leak.
-checked all other hoses and everything is in place

after doing this, i fired the car up and it was good to go but i couldnt really test drive it since personal matters had arisen. today i got that chance and it looks like its back to the drawing board. im open to suggestions, thanks!

 

did more test driving. when i get on the throttle under normal driving, it'll start to sputter and bog out, then the car will break that wall so to speak and start running smooth until it begins to sputter and bog again. afterwards the car has a bit of trouble holding idle because its got more gas in the engine. it doesnt die on me but the RPMS do drop. the car fires up fine and will idle, but it messes up once i start putting it under load.

im suspecting the ignition components, fuel injectors possibly being stuck, MAP sensor is screwy, cant be the TPS its voltages read properly. going to also check the tune on my haltech by re-uploading it. perhaps one day while i was tooling around on it i changed a setting while calibrating the TPS. starting to run out of ideas here, cant be the engine going bad either. at least thats out of the question

 

Let me know if you find a solution to this, will be following the thread. Im having similar issues.

Cam

 

hey Cam, to let you know what i got im running a single turbo set up with a haltech platinum sport 1k ECU. turns out yesterday while running tests the coolant temp sensor was giving false readings to the laptop and it made my car overheat since the radiator fans never turned on. i caught it in time luckily, the car fired up pretty quick after i let it cool off. no smoke out of the exhaust either.

cold start up this morning was ok though revving it was choppy since it was sort of flooded. after clearing the fuel out some, was able to maintain steady idle, still has strong pulses on ignition. it also smoked a bit from unburnt fuel so came back to work smelling like a boat (love premix lol).

my next move is:

-check fuses regarding fuel/ignition
-check plugs for fouling
-replace coolant temp sensor

so far everything ive fixed on the car did need repair, but it hasnt made the car road worthy just yet. after TPS recalibration it drove a hell of a lot better, but that sputtering still occurs with pig rich AFRs diving into the upper 9s range even, not just 11s. at idle im seeing mid 11s to low 12s. if i rev it, it'll go to low 11s upper 10s. what are you experiencing?

 

Boost leak maybe?

 

i found an unplugged vacuum line from lower intake mani to a port on the engine block beneath my secondary fuel rail. i honestly thought that'd be it...but wasnt lol. regardless it wasnt time wasted at least, but man was i disappointed when that sputtering occurred again

edit: i checked my vacuum lines again, everything is good. got a feeling its that CTS causing this but my hopes arent up at all

 

Bogging is usually too much fuel, or dodgy ignition.
You could have a stuck injector, also check your plugs, wires & coils.
Oh and that ground that is near the spark plugs on the front housing..(i think its a bit above them? i forget), give that a good clean to.

 

yeah i hadnt thought about that ground, i know which one you're talking about. gonna get back to work on the car today, so ill be sure to check that out. ill look over the ignition components as well, thats next on the list for sure.

edit: reason im also suspecting the coolant temp sensor is because of the haltech ECU. its wired up to it, the sensor has been screwing up losing signal on and off. when its off, the temps read the car being at 14F so that should make the ECU flood the motor by dumping more fuel in thinking its cold.

 

Try to set the coolant temp fuel correction map to zeros across the board. see if that fixes it.

 

the issue has been identified and its gonna take some time to fix it up. i went ahead and just said **** it let me do a compression test. turns out the motor is low on both rotors so the way i see it the overheat probably killed the apex seals. the way the car is looking, i believe i can re-use most of the engine so its not so bad, still starts up and is able to idle so i went ahead and put it into hibernation. will have this engine rebuilt before october

 

Hey Wolf,

Sorry I was on vacation a little while! Im having a similar issue where the car will just go mad pig rich and sputter/hit a wall when I give it anything past a 1/2 throttle. Idle evens out fine right after and it runs great otherwise.

 

welcome back, hope your vacation was wonderful! if i was you man just compression test your car. get that done before you do anything else just so you can get the possibility of engine damage out of the way. if your engine is in fact damaged and you need a rebuild, best find out what caused it so you can avoid the issue again.

 

Thanks! I did a compression test first thing and everything is tight and right on all faces for both rotors so thats not an issue.

I suspect a grounding or ignition issues, I have a brand new OEM ignition setup and a PowerFC which I anticipate will fix the issue! Will update

 

sounds good man, hopefully it is ignition issues

did you get new spark plugs as well? i will post here again after my engine is taken apart to find out what really happened. ive seen a few other threads where ppl have had this issue, so its best to see what it can eventually culminate into.

meanwhile, i got big plans to upgrade the cooling aspect of the car. vented hood, duct on rad, shrouded fans with higher CFM, adjust on the haltech UI to have them click on at 185F rather than 190F.

before the engine went, id see 180-185F all day on highway, then it'd rise to around 205F sitting in traffic or idle while waiting to go to grid at AutoXs. really im finding it ironic that regular driving is what caused it to go out rather than boosting the **** out of it. methanol injection works wonders lol

 

Yea its got new plugs and wires in it, new fuel filter, DP, intake, exhaust, emissions delete etc...

Ill have the ignition in and the PowerFC in this weekend so will update soon

Cam