Idle issues
09-20-2014, 05:57 PM
#21
Advanced
Member Since: Aug 2014
Posts: 67
Likes: 0
Received 0 Likes
on
0 Posts
If anyone has Scan9495 please try opening this file. http://www.megafileupload.com/en/fil...03119-csv.html I am having problems opening them myself. But here's the issue: after a cold start after a minute, it will idle down a lot if I raise the rpms, and a lot worse when i turn on the ac. I cleaned the IAC, MAF, air filters and it helped. I even replaced the IAC and it persists. After it's fully warmed up I don't really have a problem with it. This morning I turned on the ac during this cold start and it just kept stalling.
From the scan, at idle my tps voltage is .69. At WOT it is 4.47(100%). An MAF line trouble code keeps flashing in and out but I believe it's just related to the issue which is possibly the tps. Is this adjustable or does this sound like a bad tps to you guys?
From the scan, at idle my tps voltage is .69. At WOT it is 4.47(100%). An MAF line trouble code keeps flashing in and out but I believe it's just related to the issue which is possibly the tps. Is this adjustable or does this sound like a bad tps to you guys?
Just my 2C, but I was helping a buddy of mine with an Fbody TPI that would run and cut out, and in the end it turn out to be the MAP (Max Absolute Pressure) sensor. However, if your MAF is giving you the code, it could have gone bad, or your cats may have a restriction, seen that 2. Your TPS reading were within specs even before replacing.(0.54 V +-0.075 V), though I was told that for the 90-91 it could be 0.71? which I doubt.
In another
09-20-2014, 10:29 PM
#22
Instructor
Thread Starter
Member Since: May 2014
Location: Florida
Posts: 237
Likes: 0
Received 0 Likes
on
0 Posts
I had already called up Granatelli about my MAF. He said they usually just work or they don't, but if I wanted it tested it would be I think it was $75. SO, it could be the MAP but I have a few things to do after another guy looked at it and gave me a few pointers of things that may be contributing. No cats on this car.
09-20-2014, 10:56 PM
#23
Advanced
Member Since: Aug 2014
Posts: 67
Likes: 0
Received 0 Likes
on
0 Posts
I had already called up Granatelli about my MAF. He said they usually just work or they don't, but if I wanted it tested it would be I think it was $75. SO, it could be the MAP but I have a few things to do after another guy looked at it and gave me a few pointers of things that may be contributing. No cats on this car.
What year is your C4? Mine is a '90. Is your TPS adjustable? Mine is, and I set it at 0.64 with my timing at 8*, and TPS idle at 450-500 in Neutral. MAP are cheap, less than half a C note.
09-21-2014, 12:37 PM
#25
Advanced
Member Since: Aug 2014
Posts: 67
Likes: 0
Received 0 Likes
on
0 Posts
If you ever have to replace it again, get an adjustable one, or make your own by elongating the holes with a drill/file. You can use a drill with a small mill and finish it with a rat tail file. Get a TPS test connector with a good old fashion digital volt meter, and dial it in, after you set your TB min. idle.
12-14-2014, 10:18 PM
#26
Advanced
oh I expected it to replay in the same program like datamaster does. I see what you're talking about now. I selected 'commas' on the import window when it asked and now it's clear. I also just downloaded it from the link so the link is working. This is from yesterday when it kept stalling so it says RPMS at 45 but it's really at 0. I don't know why it says that.
In case anyone is still reading this:
The Scan9495 app does replay the CSV log file. Make sure the file is from the same version of the app. When I loaded it into the app, there were many strange looking readings, so it's probably a corrupted file or has bad data from the pcm.
The pcm states the rpm as 45 when the engine is stopped. That is normal. A Tech II shows the same. I believe that is to be sure a value is being read and not nothing (zero).