VR6 Idling issue

[tassie_euro_mk1]

Hey guys

Not sure If this topic has already been bought up.

My VR6 has trouble idling. Usually happens when its warm and when I come up to the lights or just idling.

It goes down to about 300rpm, picks itself back up. dies down again. sometimes it just stalls. It also runs rough on some occasions.

The old man is coming up on the weekend to check it out but you guys are full of knowledge also so... Any Ideas?

Cheers
Eric

[bboyskidz]

i had a similar issue.

turned out to be a filthy throttle body and a leaking vacuum hose... $450 later (including a new starter motor as well) she is running like a panther (i was going to say cheetah but my car is black :j )

not sure if it will be the same on a VR6 coz i have a 1.8L CL... worth a look though...

[Tim]

the ISV damper on my vr6 developed a leak. Its a small plastic box looking thing near the back of the throttle body. Did a similar thing to whatyoure describing. It is possible to bypass it if this is the case. All it does is make the ISV a little quieter

[The_Hawk]

Mine is doing something a little different, revs seem to be staying up. Also they don't seem to be dropping as quickly as they did. (mind you it seems to come and go a little).

I kept thinking the MAF wiring, so I added a little heatshrink to seperate the wires where they were fraying, not perfect, but good enough for a job in the dark last night:


Still happening... will look into it a little bit more and see what happens, any suggestions are welcome.

[tassie_euro_mk1]

thanks guys.

The ISV damper box that you describe Tim, does make a loud hissing noise. Louder than usual I noticed. Ill check that out today.

Im a bit concerned that it could be a head gasket because the cooling system seems very pressurised.

[frank_grimes]

had the problem with mine...found the alarm installer losened a vacume hose when he put the alarm in...

[Golf Houso]

Run it through a diagnostic, might be a faulty crank angle/hall sensor. VAG cars are notorious for this failing, and its not cheap either 600 + for the two...

[tassie_euro_mk1]

Thanks for your input guys. Lots of suggestions.

My dad the mechanic came round today to scope it out. Looked at the ISV damper unit thinking for sure this was the problem.

Nothing wrong with. No air leaks.

With seeing the symptons and lots and lots of testing with a voltage meter we found the problem to be a stuffed Air Mass Sensor

Its was weird because dad works for Mitsubishi and Mazda and said that he was talking to a Bosch rep this week who said they sold heaps of air mass sensors for a certain model Mazda. Apparently the sensors cant handle the hot weather we have been having.

So more tests to come. If it is the ams then ill have to get one.

Ill let you guys know how it goes


Thanks
Eric

[vwthunder]

Yeah, I would like to know how you go, hopefully it isn't too expensive as I know things like the 02 sensor are not cheap
I am having the same problem with my car, and it dosen't seem to throw any codes.
Maybe I will do the same thing as you, when I find out what that is

[tassie_euro_mk1]

Hey guys does anyone know what the voltage output should be on an Air Mass Sensor?

I need to determine whether it is actually the sensor and the voltage output should clear that up for me.

Cheers
Eric