tsi running bad

richfiero · Post by **richfiero** » Mon Oct 03, 2005 6:40 pm

my freind has a 1990 talon tsi and it runs bad with the idle jumoing all over the place from a cold start and when the car warms up it idles a little better but still sucks. he broght it to a tech and he said its the mass air sensor. I would think that it would not be this because the car runs off of stored fuel maps when warming up and doesnt run off the senors.
So i was thinking it has somthing to do with fuel or spark and not the mass airflow. Just want to know if you guys have any idea's on what it could be.

Fast88Fiero · Post by **Fast88Fiero** » Mon Oct 03, 2005 9:07 pm

Is it hard to start also? Check engine light on? When I bought my TSI the ECU was bad and it ran like shit. I've also had a coolant temp sensor go to shit and cause hard starting.

The Dark Side of Will · Tue Oct 04, 2005 10:41 am

The only sensor the PCM doesn't use when cold is the oxygen sensor.

DSM's with modified MAF sensors frequently have idle issues. A damaged one wouldn't necessarily be any different.

trigger · Post by **trigger** » Fri Oct 07, 2005 3:24 pm

go to vfaq.com and use the idle surge checklist. dsms are whores. well, cars in general are, but maybe you can find something useful on there. its a common dsm problem.

bryson · Post by **bryson** » Sun Oct 09, 2005 8:46 pm

Check for vacuum leaks -- I know it's simple, but on any car with a MAF it's the first thing to check.

richfiero · Post by **richfiero** » Sun Oct 09, 2005 9:27 pm

it was the maf sensor its runnin good now. thnx for the help