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-   -   HELP! My car won't start!! (https://ls1tech.com/forums/pcm-diagnostics-tuning/733605-help-my-car-wont-start.html)

Luna Jun 17, 2007 05:24 PM

HELP! My car won't start!!
 
Sorry this isn't 100% tuning related but it does have to do with the PCM and I know you all know alot about that.

Ok, so after installing my wideband my car won't start anymore....

It cranks but won't start, pretty sure its not getting fuel either as I don't hear the fuel pump turning on when I turn the key on.

HPTuners can't find the computer either. I did remove the computer and reinstall it to get to the firewall grommet.

Is it possible I put the PCM back in upside down and plugged the harnesses back into the wrong place? Is the blue harness supposed to be on the top or the bottom?

Otherwise is there a way to test whether I fried the computer or not ?

Shallow Bay Jun 17, 2007 08:38 PM

Did you remove the PCM from it's bracket? If not, then there's no way you could of installed it upside down. However, it's still possible you plugged the connectors into the wrong location. On the 98's, the blue connector goes to the upper portion of the PCM. If the connectors are in the wrong location, switch them and check the PCM BAT fuse under the hood.

67rsss Jun 17, 2007 08:52 PM

It is not possible to plug the connectors in wrong, they are keyed. I would look at fuses. You may have wired the widebands wrong and blown a fuse.

Luna Jun 17, 2007 09:13 PM

I did remove it from the bracket when I was trying to wiggle it back in thats why I'm thinking maybe I put it in upside down.

If I remember right they are keyed exactly opposite of each other so if the PCM was put in upside down I would think its possible to put them in the wrong place?

I'm gunna give this a shot tomorrow, hopefully thats all it is

67rsss Jun 17, 2007 11:19 PM

No way. Blue is keyed onthe fifth pin and red is keyed on the seventh. You could only get it in the bracket one way as well.

Shallow Bay Jun 18, 2007 02:20 AM


Originally Posted by 67rsss
No way. Blue is keyed onthe fifth pin and red is keyed on the seventh.

While it's true that they are keyed in different locations, it makes no difference. If you flip the PCM upside down, the key positions remain the same. If the PCM was installed upside down, the connectors would still plug in. This would result in the connectors being in the wrong location and the problems Luna was describing.


Originally Posted by 67rsss
You could only get it in the bracket one way as well.

I think your referring to a later PCM. The 98 PCM's are almost symmetrical and they could easily be installed the wrong way in the bracket.

Luna Jun 18, 2007 09:48 AM

Well my car just started!!

Its exactly what I said it was, the PCM was in upside down allowing the connectors to be plugged into the wrong place.

Maybe its just a 98 but the harness connectors are keyed exactly opposite of each other meaning if the PCM is in the wrong way they will still plug into the wrong spot.

It is possible to put the PCM in the bracket both ways for a 98 at least.

The moral of this story is, leave the f*cking PCM IN THE BRACKET!! I found its actually pretty easy to get in and out if you just disconnect the passengers side hood strut and move all the wires out of the way.

THANKS SO MUCH GUYS!!!

67rsss Jun 18, 2007 12:09 PM

Wow, they fixed that by 2002. The PCM I am looking at is keyed so that you could never install it wrong, and you would never get this box in upside down. Must have been a problem in the beggining and they took care of it permanently. GLad to hear you car is running!

Shallow Bay Jun 20, 2007 01:09 AM

Good to hear it was a simple fix. Did you blow any fuses?


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