Ok guys Im new to this forum but need some help please..The problem is about a month ago I left work on a 20 some degree day and the car died after about 3 blocks just like you turned the key off..It finally restarted about a half hour then ran like normal...I took off and it died again going down the hwy about 6 miles later..The car fires and runs about a second then dies everytime..I towed it home and had a local shop come out with his anaylizer and was showing no codes..Then it starts for him and runs perfect..I took it for a drive and it went about 6 miles and died again. No sputter,jerk but just shuts off...He thought it was the ignition control module so I replaced that with a ac delco and would not start..To make a long story short I have replaced the crank sensor and the BCM..The shop reset the passlock system also..Sometimes it dies after a half mile cold..Never had it die while just sitting..I have went through all the wire connections and cant seem to find any loose connections,corrosion or loose grounds or anything..Have moved wires around while running and nothing has made it die untill its driven. Fuel pump pressure is 52..I have tried a different key but it doesnt have a chip in it..Would a bad ignition switch do this? Im loosing faith in GM right now..In the past it seems if you mess with the BCM it sometimes starts but now I cant even get it to start..Im tired of having to tow this car..The car has 139k miles and I have put on over 100k myself so I know the history of this car..Any ideas would be appreciated...Thanks

 

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i am suspicious that there are no engine codes... makes me think there is something wrong with the PCM

it deff sound electrical. Try this... Start the car and put the E-brake on. put chalks on the wheels or something to make sure it doesnt move. or have someone sit in the car with the foot on the brake, then put it in drive. if the car is still runing, go under the hood and tap the PCM. it is under/inside the air box on the driver side of the car. My guess is the car will die at this point. if it does inspect the wires going to the PCM there are 100 of them. and make sure the connector is screwed in all the way. if the connections are good there is a chance the PCM itself is bad. i would go on ebay and buy a PCM and have the dealer reprogram it for your year and car. or Buy a performance PCM for your car! send your old one in as the core and get a new PCM and a mod all in one!

 

Ok thanks z34Phoenix and Kidspace for the replies...It does seem to be something to do with the PCM but so far havent figured out what though..I had it in the shop a couple times and everytime he messed with the PCM it would run for a bit until I drove it..I towed the car home then and figured I could do as good as he was doing..I inspected the wire connections at the PCM very closely..I found one wire that was slightly loose I believe it was #19 but was a red wire..I pushed it in and I got 14 miles before it died..I since have tried messing with that wire and connection and it will not start for me at all now...The PCM I got was off of Ebay and its a used PCM that they program to your vin #..They are suppose to warranty them for 1 year but it seems odd that 2 PCMs would do exactly the same thing but its possible..I have did alot of research online and have not seen anyone with the same problem as I am having..Close but not the same..The last time it died I noticed as its slowing down the tach was reading about 1000 rpms then quit completely..One thing I have noticed to when I try and start it the tach never moves but not sure when it should read because it only runs a second or so..Im wondering what a bad cam sensor would act like or is it in the ignition switch? If I can get it to run again I will try tapping on the PCM...Thanks again for the help..

 

What company made the PCM that you purchased off E-Bay ? Have you contacted that company ? Are they giving you assistance ? When did you install it ? Did you already replace your PCM before & then replaced it again ?

After you installed it, did it run OK ? For how long or how many miles (Estimate) ?

Please post additional information so that our expert tech's can advise...

Good Luck & keep us updated...

 

I purchased this through spareecm out of Ohio...Its been in only a couple weeks and I replaced it after all this problem started...It didnt change anything so I figured it was an ok part and i just had another problem..I had the shop put it in and at first it wouldnt even crank over the car and he reset the passlock and it worked after that only untill I drove it..The guy at the shop made me test drive it and I made it a half mile that time doing about 25 through town..I have not recontacted them..This would be only one I have replaced..It runs super when its running just like normal then its like you shut the key off and then thats it...

 

I suggest you contact the company or revist the tech that did the install...

Also check out the below link (Good Luck 4-Sure)
ECM TECH INFO - FAQ - HOW TO KNOW YOU NEED AN ECM
click above link

 

After letting this sit over the winter and digging back in I finally figured this thing out....the MAP sensor...replaced it and the car fired right up I put the old one back in and it wouldnt start..The new one back in and it runs..I have put several hundred miles on it with no problems!...

 

I know this is an old thread, but my 2002 MC is doing this EXACT same thing. I will investigate the MAP and see what happens. Thanks for posting the solution you found for your problem.