Some advice on a boost problem please.
10-19-2005, 10:17 AM
#1
New Member
Thread Starter
Join Date: Aug 2002
Posts: 96
Likes: 0
Received 0 Likes
on
0 Posts
Some advice on a boost problem please.
Hello all,
Here is my issue. I have a 91 200 TQW that has been going into limp mode. I get about half boost, it seems to spool up normally but it climbs no further than 1.1. I have an idea what is causing it, I recently replaced a temp sensor that had coolant leaking on it an I believe the car was running lean as a result. I have not checked my plugs to see if they are fouled yet. Some mornings I start her up and she runs at full boost others I will be in limp mode. Does anyone know how the ECU reverts between normal and limp mode. Is it a dynamic thing where the ECU examines running conditions and will enter limp mode when less than optimal conditions are detected? At what point does the ECU reset itself so that boost is again normal? Just trying to figure out why the car seems oscillate between normal and limp modes. Sorry for carrying on an thanks for your help.
Hassan
Here is my issue. I have a 91 200 TQW that has been going into limp mode. I get about half boost, it seems to spool up normally but it climbs no further than 1.1. I have an idea what is causing it, I recently replaced a temp sensor that had coolant leaking on it an I believe the car was running lean as a result. I have not checked my plugs to see if they are fouled yet. Some mornings I start her up and she runs at full boost others I will be in limp mode. Does anyone know how the ECU reverts between normal and limp mode. Is it a dynamic thing where the ECU examines running conditions and will enter limp mode when less than optimal conditions are detected? At what point does the ECU reset itself so that boost is again normal? Just trying to figure out why the car seems oscillate between normal and limp modes. Sorry for carrying on an thanks for your help.
Hassan
10-19-2005, 10:31 AM
#3
New Member
Join Date: Sep 2005
Posts: 445
Likes: 0
Received 0 Likes
on
0 Posts
I think it's dynamic
I think (iirc) that the ECU is constantly watching things and making adjustments, and if it determines that it is unable to adjust for some condition, then it reverts to "limp home mode"...
If I have to guess, I'd say that the other folks here would advise you to check for a vacuum leak, broken hose or a plugged hose (possibly the hose that connects to the ECU?)
As for reset, I think it's as soon as you turn off the ignition switch?
If I have to guess, I'd say that the other folks here would advise you to check for a vacuum leak, broken hose or a plugged hose (possibly the hose that connects to the ECU?)
As for reset, I think it's as soon as you turn off the ignition switch?
10-19-2005, 11:24 AM
#6
New Member
Thread Starter
Join Date: Aug 2002
Posts: 96
Likes: 0
Received 0 Likes
on
0 Posts
Re: put in wrong temp sensor?
I was having the problem before replacing the temp sensor. It was replaced with the correct part but I did notice that the car was running lean for a period of time, white smoke on start up and heavy gas smell after driving, and thought this may have been due to the faulty sensor.
