My brother in law owns this car.

I did a complete engine swap on a 99 S70 and know it inside out. That was for a pal back in Oct. 2009. The 98 is a different animal.

Anyway.....car will run fine but at times it will idle very poorly and stall when coming to a stop or just while in motion.

The check engine light is on so I will have codes pulled.

BUT...before I do....what are the common idle problem areas on a 98?

MAF, IAC valve, O2 sensor telling engine to run too rich?

Thanks.

 

Yes, the '98 is a different animal; less complex and easier to work on IMO..

Pull the codes for sure; that should give a clue. But from the symptoms it sounds like it's running out of gas. Right after it dies, does it restart right away? More background info please; how many miles on the odo, etc.

 

My guess would be ICV. Likely a loose vacuum just under the cover if it still has one where the throttle cable go near the valve. Ours was torn on the lower side. Caused some rough idleing, stalling when coming to a stop at a light, slugish accelleration I think.

I don't know why some do it but they tighten the hose clamps to darn tight, causing the clamp to cut through the line after a while.

 

Okay....we went from bad to worse today.

He took it to Autozone and they said his MAF was bad. This is a car he will not keep long so we did not want to buy a new one. We got 2 used ones and 2 fuel pump relays for $19 and change.

I took the IAC off of the car and sprayed it with MAF cleaner....the liquid came out kind of dirty and evaporated. A swap of the MAF.

It started and idled well for about 2 minutes....then died in park.

Now it will not restart with any combination of MAFs and relays. It cranks and is getting fuel because you can smell the raw fuel coming out of the tailpipe....YES this is bad for the cat. to do that so I quit for today.


VADIS is so frustrating to look at....I could find no diagnostic bench test for the MAF or IAC. In most all cars you can test the IAC by checking for resistance between pins that are within a range. In some cars you can do the same with the MAF to test it.

How do I test these parts?


Anything I am overlooking?



Miles are 95K and prior to this getting worse....yes it would restart immediately.

My brother in law has never been to a junkyard or done anything beyond oil changes so it's all on me.


RSPI.....I did not see a smaller vacuum line in that area. Where does it feed to?

Thanks