Engine not running

GOOSENEC70

MEMBER
1996 BUICK REGAL
139,000 MILES

I have a 1996 Buick Regal 3.1. It has a P0300 code. Plugs, wires, module, coils packs, fuel filter have been changed since the SES light came on. Nothing has changed. I took it to my automotive class. The fuel pressure was at 34psi while running, but the specs says it should be 41-47. My instructor told me since the FPR wasn't leaking, my pressure problem was most likely from the fuel pump. Changed the pump with no difference. I've changed all the parts myself, but this is nerve racking. It seems like something small because it runs pretty good, just has a little shutter. Compression test was fine for all cylinders. But cylinder 3 had a lot of misfires when I used the scanner in the misfire menu. The history on this car: came from a tow yard not running. Complete head and valve job was done. After all of this, it still has this problem. What now? Please help.

6 Replies

RASMATAZ

MECHANIC
75,992 POSTS

It sounds like the exhaust could be plugged here is a guide to help you confirm the issue.

https://www.2carpros.com/articles/how-to-test-a-catalytic-converter

Please run down this guide and report back

Cheers

SPONSORED LINKS

Was this

answer

helpful?

Yes

Friday, December 21st, 2012 AT 8:19 AM

GOOSENEC70

MEMBER
4 POSTS

I forgot to add that all injectors were changed at the time of the post. I have tried checking for vacuum leaks, but not with a smoke machine. I took it to the shop that I used to go to ( before I worked on my own cars), I told the guy everything I did. He didn't want to take it for a diagnostic. Back to the drawing board. Thanks for your reply!

Was this

answer

helpful?

Yes

Friday, January 18th, 2013 AT 5:52 PM

RASMATAZ

MECHANIC
75,992 POSTS

You don't need a smoke machine use a vacuum gauge this gauge tells you a lot about the engine and also is the fuel pressure within specs? What about the exhaust?

Was this

answer

helpful?

Yes

Sunday, January 20th, 2013 AT 10:44 AM

GOOSENEC70

MEMBER
4 POSTS

I checked the fuel pressure Friday, it was 38 psi. I took the vacuum hose off the for, hit the throttle, it jumped passed 45 to 50 I think. But I've tried leaving the hose off to see if gas comes out. 10 to 15 mins, no gas. I got a hard start, then cut off on Friday. It started, but was stumbling real bad. I got a blinking ses light, then it held. I got home to check the light, which was a p0300. This was after driving 80 miles on the freeway. Some guy told me that the crankshaft sensor or camshaft sensor may be acting up. Said it was where my hard starts we're probably coming from. I hope this info helps

Was this

answer

helpful?

Yes

Sunday, January 20th, 2013 AT 4:43 PM

RASMATAZ

MECHANIC
75,992 POSTS

Sounds like you either have a leaky injector/s or the fuel pump is weak-it has to be on 41-47 psi when you turn key on-also you need to check the engine compression, spark plugs and injectors-also the cam and crank sensor-