I've been having this on-going issue over the last several days that seems to be worsening. It first started a couple of days ago, I was on my way to work when I noticed a couple of short hiccups when cruising in 4th. It happened twice and never came back for the remainder of the day. No codes were thrown.

The next morning, the same situation happened again except that this time it was more prominent. It would sputter and hesitate under normal acceleration, it would actually misses for second or two then smooths out like normal. Originally, I thought maybe it was because my car was not fully up to running temp but as I continued on my commute (20 mins later) it was still showing the same symptoms as the day before... hiccup and sputtering while cruising.

Today was the worse. As I was leaving work, the car completely stalled when I was coming to a stop at a light. I was able to restart the car but it sputtered and sound like it was misfiring from several cylinders (Subaru like). I was barely able to move the car enough to pull over. Just as I was coming to a stop on the side of the road, the car died again. I crank it a couple of times but it wouldn't start. So I got out, pop the hood to see if any obvious was causing the issue (vacuum leak, loose IC pipe) and found nothing. I try to restart the car again and it start right up without issues. I was able to drive home like normal without any symptoms. Later on in the evening, the same happened again. Stalled at a stop sign, restarted... sputtered and then it smoothed out.

I've so far check the plug which were fine. FP idles at 32psi, pressure raises like normal and even when it was sputter it held 40+ psi. There is still no CEL.

The only common denominator is that the stalling seems to happen only when the car is cold (within 5-10 mins). However, the misses/hiccups happen randomly no matter if the car is cold or hot. All under vacuum and no boost what so ever, it doesn't happen every time and I wasn't able to duplicate the issue at will.

Mods:
Built bottom end, speed density conversion and tuned 8 months ago by English.
AMS GT35R w/ ETS IC kit, dual walbro (in tank and inline w/boost switch), 1000cc AMS injectors and fuel rail.

The car has been running perfect up this week and no additional mods has been added. I'm pretty stump and I plan on giving English a call in the am but I thought I may as well post just to see if anyone has had this similar issue before. I've read it maybe a cam or crank sensor but I thought it should have thrown a code if that was the case.

 

From reading this, It seems my car was doing the exact same thing. I fought it with it all memorial day weekend. I replaced a couple things, but what ended up fixing it, at least I think, as it hasnt dont it since, is a coolant temp sensor. I dont really get it either lol. BUt Someone had suggested it, so I tried it and it works haha. At the same time I replaced the coolant temp sensor, I also disconnected the battery, so maybe that had something to do with it. I dont know. I never threw any cel's either.

Worth a shot. I know when my car was doing it, I was ready to drive it off a bridge I was so frustrated with it lol.

Here is my thread on it:
https://www.evolutionm.net/forums/ev...-stalling.html

 

Thanks for the reply. I was actually low on coolant. I think I may have a leak somewhere cause I topped it off just a couple weeks ago and my reservoir is now empty. However, I have not noticed any coolant spots or leaks under the car where ever I parked, engine temp has been stable. I will look into this after work.

So far no issues while I commuted to work. I'm gonna be driving the car again here in a bit so I'm crossing my fingers that due to the coolant being low that it was throwing the coolant temp sensor off.

 

So i'm stilling having the same issue. In fact I was able to get it to start at a light and it took 3-4 tries, what was strange was it would hesitate a couple of times first prior when I got to the light. as I was idling at the light it just died... I was able to record the starting issue but didn't catch the stalling issue. Here is the link:


Any ideas?

 

Thats exactly what mine was doing!! lol

All I can say is try that coolant temp sensor. Its what fixed mine, that or possibly unplugging the battery for awhile.

 

OP, did you ever solve this issue?

My car is doing the same thing. Runs great then randomly doesn't want to run. I shut it off, start it back up, and it's fine. Completely random, as it does it at any temperature. But I've also gone on a 50 mile trip where it didn't do it at all.

Stumped as to what it could be.

 

Cam angle sensor going bad?

 

Hmm, I have a few extras. Perhaps I could toss one on and see if that fixes the issue. I thought that they either worked or didn't work. It's worth a try, I suppose.

 

yeah normally they do or don't work...mine was loose a long time ago after a cam swap and i tightened the nut back up and my problem was fixed

 

Can't hurt to check it. I think mine may be tune related, but we'll see.

 

^definitely a possiblity!

 

What's up guys! I'm having the same issue with my car. Except that my car in the morning while its warming up from cold start it warms up well. But, when I turn it on when going home to get my lunch break (cold start) it starts to idle real bad and misfire crazy thing is that it idles real low but still manages to stay on. What i notice is that my Air Fuel gauge drops below 14. I don't know if that matters, but just wanted to throw it out there. Well anyways ive replaced the MAF, IACV, checked for vacuum leaks, and there is no code. So I ordered the Coolant Temperature from the dealer and should be getting it pretty soon. I kind of do believe this should fix it since that sensor works with ECM to adjust fuel level according to temperature readings. If you have not replaced it, and are still having same issue give that sensor a try. From the actual dealers its aroung 80. If you work at a shop like I do it should cost around 50 something bucks. let us know if it works as I will also keep you guys updated well to those who have same issue.

 

I apologize for a very late response. After a another week of it happening at random, I end up taking it to English Racing where they adjusted my idle and cruising tune. Being it was a SD conversion, Aaron turned on a setting to increase the calculating window for idle and cruise (forgot the exact setting) but since that adjustment I have not had any issue with this. O in the end my issue was tune related rather than a sensor or a mechanic issue.