Coolant temp sensor *Fixed*

[Orange85]

Ok, for some reason I cannot remember if a bad temp sensor will cause a truck to not idle or run like crap under load. I have surging at idle and when i drive down the road i have to really ease into the gas or it will stumble all over.

The TPS, MAP, IAC. all tested good when i checked them with my Snap On Vantage MT2400 (Old but still works)

No Vacuum leaks. This has just got me stumped.

Oh and it is an 88 350 TBI

Was a fuel Pump

 

[wheels87k5]

Also check fuel filter, and EGR valve.

 

[Orange85]

Changed the fuel filter last week as maintenance. Replaced Temp Sensor and cleared codes. took it for a drive and no more stumbling, but i now have a lean code.

 

[tRustyK5]

The coolant temp sensor on my 90 caused a massively rich condition that would kill the engine dead as it approached operating temp. It was telling the computer it was -60F when it was in the low 40's.

Rene

 

[Orange85]

The guy that I bought my first 4x4 from had the same thing happen. Was a 90 Suburban.

 

[4xcrazy]

sounds like you are going through what i did awhile back, kept getting all sorts of weird codes at random, but one kept coming back more than others, that lean burn code.

turned out to be a weak fuel pump.

and yes, it ran and drove exactly the way you are describing too...

 

[Orange85]

that is what I am affraid of. When I changed the filter it was so plugged that it could have strained the pump.

 

[Orange85]

just got home from work and did a while running fuel pressure test

New fuel pump tomorrow. Gonna just cut through the floor being as it is at home now and not at work. Anyone have measurements for where to cut through?

 

[4xcrazy]

how much gas in in the tank, it's really not that difficult to do the job correctly without destruction of the floor.

 

[Orange85]

I know its not hard but it is at my house in a gravel driveway. If i could id take it to work and do it on the hoist. I really don't care about the floor. I have done quite a few fuel pumps and would just like to have easy access to the pump on here.

 

[Orange85]

forgot to add there is a full tank in there Fuel pumps never go out with less than half a tank lol