1991 Buick Century wont start

MATTYBETTS

MEMBER
1991 BUICK CENTURY
6 CYL
FWD
AUTOMATIC
27,500 MILES

I replaced the fuel pump(gets good pressure now} and also replaced the fuel regulator. But the car will not start. The injectors are getting electric as I tested them with a test light. I sprayed a tiny bit of gas into the throttle body and it started but imedietly stalled. This tells me it is getting spark. I dont know what else to do. Please help

Saturday, August 21st, 2010 AT 7:07 AM

5 Replies

KHLOW2008

MECHANIC
41,814 POSTS

Hi mattybetts,

Thank you for the donation.

Did you test the injectors circuit for pulsing while cranking?

Was any other repairs carried out prior to this occurring?

Was this

answer

helpful?

Yes

Saturday, August 21st, 2010 AT 8:00 AM

MATTYBETTS

MEMBER
3 POSTS

I used a test light to test the injector plugs, in which there was current to every one of them. I did not check the pulse. Is there a easy way to do this?
And no other repairs were done prior.

Was this

answer

helpful?

Yes

Saturday, August 21st, 2010 AT 8:11 AM

KHLOW2008

MECHANIC
41,814 POSTS

The injector curcuits are grounded by the PCM and to test if they are pulsing, you would need a noid light.

Disconnect the injector coupler and connect the noid light across the 2 terminals.
Crank engine and note if the noid light pulses. No pulsing means the PCM is not grounding the circuit and it could be bad.

Was this

answer

helpful?

Yes

Saturday, August 21st, 2010 AT 8:21 AM

MATTYBETTS

MEMBER
3 POSTS

How would I repair the short in the pcm

Was this

answer

helpful?

Yes

Saturday, August 21st, 2010 AT 1:44 PM

KHLOW2008

MECHANIC
41,814 POSTS

If the PCM is bad, you would have to replace it or send it to someone who do rebuilds on them.

Before confirming if it is a PCM problem, check the continuity between the injectors and the PCM.

Was this

answer

helpful?

Yes

Saturday, August 21st, 2010 AT 11:31 PM