1988 GMC S15 Gas in oil

1988 GMC S15
196,000 MILES • 2.5L • 4 CYL • 2WD • MANUAL
Avatar
MHC92
  • MEMBER
  • 1 POST
The truck has not been run in about six years, before it was parked it ran good. I brought it in the garage changed the oil, plugs, wires, fuel filter, air filter, distributor cap and rotor. I started it up and it's back firing and missing really bad, I pulled the dip stick out and it smells very badly like gas and it about a half quart over full. It wasn't that far over when I put the new oil in, can anyone help?
Jan 20, 2014 at 12:01 AM
Avatar
CARADIODOC
  • ✓Experienced Mechanic
  • 34,403 POSTS
Pull the vacuum hose off the fuel pressure regulator and check if it's wet inside. If it is, replace the regulator and get that oil out right away.
Jan 20, 2014 at 12:16 AM
Avatar
DOCDTC
  • ✓Experienced Mechanic
  • 53 POSTS
Hi,
If the first reply does not fix your concern, Check the coolant temp sender (CTS). It is located near the thermostat housing. If the ECM does not receive a reading back from the CTS, it's default programming is to -40 degrees. This will cause the symptoms you describe in very short order. Hope this is helpful, Keep me posted on what you find.... Doc DTC
Jan 20, 2014 at 2:43 AM
🔧 Tools & Auto Repair Parts
Find automotive tools, diagnostic equipment, and replacement parts for your next repair.
Shop on Amazon →
Paid affiliate link. As an Amazon Associate, we earn from qualifying purchases.
Add a reply
Join 2CarPros for free, one of the most advanced car repair communities on the internet. From first-time drivers to seasoned mechanics, everyone is welcome to reply, share details, and get better answers. You can add a temporary image or video first; uploads are limited to 20 MB.

Ask a new question

Frequently Asked Problems for This Vehicle