2000 V40 won't idle, not mass airflow sensor

mcage228 · Post by **mcage228** » 15 May 2010, 08:56

Hi All new kid on the block here, ? Just replaced water pump -timing belt- tensioner. Drove car 12 miles home from shop ran great. Next day drove 12 miles car then started running ruff brake gas to get it home. Does not want to idle. You can keep it running with foot on gas above 1 k rpm. I had a freind hook up his computer. Pointed to mass air flow, I cleaned it and no joy. I switched a good one from another V40 same thing will not idle. Its confirmed its not the mass airflow. Any ideas? help on what it could be?????
Many Thx in Advance

Post by **JDS60R** » 15 May 2010, 09:42

Start with the obvious.
Listen for vacuum leaks for unmetered air. Then,Pull engine cover and check cam belt timing.

What code did you get? The more specifics you give us the more we can help.

mcage228 · Post by **mcage228** » 15 May 2010, 11:14

Thx JD, Snap on computer used. A mechanic friend has it, read it and he said its the Mass Airflow sensor. Code ? Don't know when he can come back? Anyway he said get the cleaner and clean it which I did, didn't help. Then I switched the sensor out with another 2000 v40, didn't help. I did put the supposed bad sensor on the good car and it ran fine. I need to get him back. I most certianly appricaite your input trying to help. I'll recheck all vacum lines that I see. Just had the new timing belt put on initialy ran fine could it have jumped. I guess its possible but would not be a good thing imo.
Many Thx and have a great day!

Post by **billofdurham** » 15 May 2010, 15:30

Have you erased the code?

Bill.

mcage228 · Post by **mcage228** » 18 May 2010, 20:36

Hi BillofDurham, Erased code? No sir not yet, waiting to get friend with computer back here when he can. Still have to go thru any vac line I can find as JD mentioned. Wife had the car after T-belt change all fine to work. Later way back running fine then bam would not idle at lights etc. Many thx for the response much appriciated. I'll let you know what happens.

Post by **billofdurham** » 19 May 2010, 11:54

If the code is still there the car could think the problem still exists.

Bill.

mcage228 · Post by **mcage228** » 25 May 2010, 06:51

First Bill and Jd Many Thx. Bill my friend made it over with snap on computer it does not have what Volvo has I guess big bucks to get all volvo stuff in it. Cleared code. Still same problem foot on pedal to keep idle at 1k rpm. Now No check engine light would come on. He said if electrical it should show on computer. We checked vac hose's, wires tight, sprayed for head leaks,tapped on the idle control module,etc. Everytime we started it seemed to get a little better on idle, strange? Still needed foot on pedal but you could keep it running at a lower (under 1k rpm) rpm? We decided to get the car to a shop and have the vac system smoked, but at the last minute tryed switching the idle control module out from another V40 (I have two V40 2000 models both 100k-100k+miles). The car fired up and idled fine? To reconfirm we put the original back on and the car fired up and idled fine??? I had just finished flushing coolant system, changed trans fliud, changed oil using amsoil products. Got these sqaured away topped off levels adjusted, toke the car for a good run and it runs great better than it ever has. Everything smooth and very responsive. What did we do??? Nither one of us knows, Mystery fix??? Two days later the other V40 driving along 50+mph foot off pedal to slow down and it won't slow down keeps very slowly accelerating by itself . Then temp gauge max's out. Off road engine high rpm shut it down. Start back up temp gauge zero engine rpm surging to 1k+ and back turn off. Start agian rpm surging and temp maxed agian. Under hood dah (lol) looked around no leaks no signs of overheat. I had recently flushed and changed coolent with new thermostate. Started it agian and everything is fine temp rpm everything haven't had a problem since but somethings up. Do these things have a brain and like to stress you out??? lol. I'm thinking ECT sensor (temp). Anyway I've been slammed recently with problems. Had both over a year with no problems till a couple weeks ago. Anyway maybe some of this will help some one else also. I might be good at this V40 stuff one day.lol. I most certianly appriciate your time in helping me Bill. Many Thx and GLTY--------------

double_d24 · Post by **double_d24** » 11 Oct 2010, 17:42

I don't know if you are still looking for an answer, but I had what appears to be the exact problem. I replaced the MAS and still no change. I cleaned the throttle body, and no change. But on the advice of a Volvo specialist, I removed thee idle air control valve and cleaned it, and when I replaced it, my problems were solved.

Hope this helps.

dd