1999 GMC Sierra Hard WARM starting, oil pressure increases

VACANTEYES

MEMBER
1999 GMC SIERRA
V8
2WD
AUTOMATIC
223,000 MILES

Hi, I inheirated this truck from my father who passed away last year. I needed smog and it passed perfectly. I want to take care of my dads thing so I had oil changed, then {on the way home} service engine light came on. I did not use fast lube cheapo place. Called the service center who stated he probably needed fuel pump replacement from what he observed, for 750.00. He also stated it would not slowly worsen it may suddenly just stop as I'm driving. The truck did have difficulty starting and we bought new battery now it takes a couple cranks more when warm. I don't have 750.00, the only man in my life is gone, and I dunno I don't feel I can entirely trust this guy. I trusted the place but "my" mechanic doesn't work there anymore. Also I checked through dads receipts; he had new fuel pump replaced for 700.00 12-06, dad went into hospital 12-07 the truck sat a year. Could the fuel filter go bad that quick? {No warranty}
Secondly oil pressure increases on acceleration, just curious if that's ok?

3 Replies

JAMES W.

MECHANIC
2,394 POSTS

The oil pressure gauge will normally rise with engine rpm, this is ok as long as it doesn't go too high or too low.
Do you what code tripped your check engine light? If you can find out and let us know, it will help.
On the fuel punp. For $750, I would want to know for "sure" it's the fuel and not just an expensive shot in the dark. Please advise.

SPONSORED LINKS

Was this

answer

helpful?

Yes

No

Saturday, December 13th, 2008 AT 3:06 PM

VACANTEYES

MEMBER
3 POSTS

Well of course on the way to get the stupid fuel pump before asking you the check engine lite went off. The car seemingly runs well, except if you stop and go for a few places then maybe you'd have to crank 2 times. Thats why we bought battery 2 months ago when I got truck, they did check first said battery bad. There was no lite then. Dad had all reciepts took great care of. But what scares me is the guy said when it goes it will just suddenly, no warning, stop. Like on a freeway etc. I'd like to not to kill my children, and also not throw 750.00 away. Also reading lots of articles people replace fuel pumps 2-3-4 times in a month, so I figured IF the pump I need OEM for more money. My 16 teen boy with 1 year auto shop said maybe fuel filter and we could do? But shouldn't something showed on smog check? I believe all upkeep is done, just the one symptom, that perhaps be caused from sitting a year?
Also, thx about oil gauge changing, never saw one move so much its stays at 40 goes to 60 on acceleration and back to 40 stopping.

Was this

answer

helpful?

Yes

No

Sunday, December 14th, 2008 AT 11:20 AM

JAMES W.

MECHANIC
2,394 POSTS

There are dozens of things that can go wrong on a vehicle going down the freeway other than a fuel pump. Fuel pumps, as a rule, are not intermitent, They either work, or they don't. The FP relay can be, but it's rare. 40 to 60 lbs oil pressure is great, indicating a good strong motor. Also, whatever triggered your check engine light will still be stored in the ECM memory. You could have the ECM scanned and retrieve the code. Autozone and most major parts stores will scan it for free. But, I wouldn't be too concerned unless the truck acts up.

Was this

answer

helpful?

Yes

No

Sunday, December 14th, 2008 AT 12:35 PM