Stall/Rev Drop While Pulling Away From a Stop

TheCynicalCanuck · Post by **TheCynicalCanuck** » 23 Nov 2016, 00:17

So after a day of on and off driving my 95 Turbo seems to being having some strange problem. First the coolant gauge started going haywire going up and down slowly and once I was at a red light I tried to pull away normally only for it to stall. In order to get it off the line I had to throw gas at it like it was a manual gone bad or it would spudder out. Once I got home the rev's started going wild, they would fall down to 500 then shoot up to 3000 without any input from me. I'm having a friend come out with a OBDII scanner tomorrow and I'll post any codes we pull but there was no check engine light at all.

Here's the idle issue that I was speaking of.

Ideas?

Edit #1: The car also accelerates it's self without any input from me and it was difficult to start needing me to put the throttle down to get it started.

Post by **abscate** » 23 Nov 2016, 05:23

Fixed that user name for ya!

Your car has all the trappings of a big intake leak that is screwing up metering , induction, etc

Codes won't help until The car runs close to decently, you will get lots of spurious codes if you need to mash the pedal to start and run.

There are a couple of prime suspect hoses on the vacuum tree and on the idle air valve ..start there

TheCynicalCanuck · Post by **TheCynicalCanuck** » 23 Nov 2016, 14:08

abscate wrote:Fixed that user name for ya!

Your car has all the trappings of a big intake leak that is screwing up metering , induction, etc

Codes won't help until The car runs close to decently, you will get lots of spurious codes if you need to mash the pedal to start and run.

There are a couple of prime suspect hoses on the vacuum tree and on the idle air valve ..start there

If i need to I could pull the ICV from my 94 base 850, would that be a fairly easy way to check that? And the vacuum hoses could cause this erratic of an idle and stalling?

Post by **kahl** » 23 Nov 2016, 17:50

+1 on the vacuum leak, but for giggles disconnect the MAF sensor located on the large tube from the air box and see if things settle down.

TheCynicalCanuck · Post by **TheCynicalCanuck** » 23 Nov 2016, 19:00

kahl wrote:+1 on the vacuum leak, but for giggles disconnect the MAF sensor located on the large tube from the air box and see if things settle down.

I tried disconnectimg the MAF and it just stalled after like 5 seconds. I did get a OBDII scanner ought and it put out codes for the MAF and the Coolant temp sensor.

s10lowrider1994 · Post by **s10lowrider1994** » 23 Nov 2016, 19:48

MAF code is probably because you unplugged it. I usually go at the engine bay with puffs of starting fluid to find vacuum leaks.

TheCynicalCanuck · Post by **TheCynicalCanuck** » 23 Nov 2016, 21:28

I think my first thing to do will be the coolant temp sensor. When I looked at the live feed on the OBDII scanner it was showing a temp of -40C, which is likely the reason why the engine runs so rich and revs.

TheCynicalCanuck · Post by **TheCynicalCanuck** » 24 Nov 2016, 02:43

I pulled the IAC and took some pictures of it, looked pretty clean, also took a picture of the OBDII scanner showing it displaying -40C and when the engine randomly rev'ed it's self to 3200rpm