I just recently got my TGP back on the road....(after numerous altenator problems) while installing the altenator I kinda broke the vacuum port on my map sensor....OOPS!!!  I replaced the map sensor with one from another GM car.....now every since when i start my car it shuts right back off like in 5 SECONDS....If it does stay running...it IDLES like pure shit...(sounds like it has a large CAM in it....) While running the SES LIGHT comes on and dispalys codes 33 and 34...I reset the computer by dis-connecting the NEG. side of the battery for a couple of hours....now only code 33 displays!!!  Car barley runs and stalls when car is put into gear.  Someone please help!!!!! (by the way....my TGP is setup like a stock grandprix right now...meaning i have no TURBO..so its running rich since it contains the TGP computer.....)  thanks.....SEAN

I'm new here and all but sounds like you have solved the problem with your last statement.  I had the same problem (minus the codes) with my 87 GN when I ran it with out the turbo hooked up.  Was it running fine without the turbo before this problem came about?  Another thing, is the map sensor compitable with the computer?  I use a LT1 maf on my GN but to do so I have to use a transulator for the computer to understand the "language" the maf sensor uses.  Hope that helps.

Let back up here. The turbo has boost. A normal MAP sensor can't see boost. The TGP map sensor can. A map sensor is the main fueling sensor for the car. What car did you get the map sensor from as they are NOT all the same.

That is probably your problem. THe car should run fine without the turbo hooked up.

The map sensor came off an oldsmobile cutless(same body style) it also had the 3.1 non-turbo....it is a 1 bar map sensor.  the car was running great before i broke the original turbo map sensor.  Any other ideas? thanks..Sean

I would agree with Chris.  It is probaly the MAP sensor.  They are different for other cars.

A 1-bar map sensor isn't going to work on a TGP very well  :wink:

Get another 2bar map(easy to get, Autozone has them cheap. Haven't checked NAPA) or change the mem cal to a N/A cars one.

THe 2bar map starts between 0 and 5 volts(2.5v) and the 1bar starts at 0 volts.  So the fueling is off ...way off.

i checked on a map sensor and that bitch was $85....that I dont have right now...what other cars come with 2 bar map sensors?

I should have a used 2 bar map. Email me about it if you are interested.

Both the TGP and the Turbo Sunbird have them...good luck scoring eathier one in any Auto Recycler. They are both rare cars.

Just buy Chris A's.

I also believe that the GN's have a two bar map for the boost "lights" but i doubt its interchangeable. I'm 99% that the sunbird and tgp are directly interchangeable. Also the Sy/Ty prob has a 2 bar, i don't believe they use a MAF for fueling. They might have a 3bar, the TTA has a 3 bar too, but its all speculation!  :wink:

Autozone has the MAP sensor

WELLS MANIFOLD ABSOLUTE PRESSURE SENSOR for a 1989 PONTIAC GRAND PRIX

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