4.3l vin w 1994 s10 it idols at 500 and jumps 1500rpm and loading up on fuel help!!!!!

[nicolef92]

I have a question ..at a idol my truck has very low oil pressure like in Orange ...but when I give gas goes up ???

[NHRA]

Originally Posted by nicolef92

I have a question ..at a idol my truck has very low oil pressure like in Orange ...but when I give gas goes up ???

cant remember right off hand ,,,but im thinking oil presure should be 40psi @ 2000 rpms
someone correct me on that.........lol

[nicolef92]

Ok Ty

[j cAT]

Originally Posted by nicolef92

I have a question ..at a idol my truck has very low oil pressure like in Orange ...but when I give gas goes up ???

the oil pressure if the engine is not worn should be 35-60 psi. at the idle speed when hot it should be 35-40 psi, at road speed 40-50 psi .

if below 20 psi at idle the engine is worn . below 15 psi it is not long to fail.

[nicolef92]

Long to fail???

[NHRA]

Originally Posted by nicolef92

Long to fail???

pretty sure the rpm matters idel is only like 800 rpms
so it cant be right 40 @800 rpms

[nicolef92]

At a idel not is line before Orange mark..it used it idel at 1000rpms 40 psi ...now its 700 or 800 psi and like I said line before Orange ....Idk Wats wrong with it..check engine light is on gonna check for codes tomorrow .....

[j cAT]

Originally Posted by nicolef92

Long to fail???

normal idle rpm is 600. if at 800-1200rpm then you have a vacuum leak. the computer is trying to adjust for a correct mixture. too much air will cause the computer to add more fuel then the rpms go up.

using a vacuum guage locate leaks. replace any cracked vacuum lines.

oil pressures at idle below 15 psi would mean the engine is quite worn,the engine will soon lock up because the oil will not properly flow to all the components. a good engine will have 40-60psi over the complete rpm operating range. 20psi is the point of the engine lasting if oil is replaced at the proper intervals using a quality oil filter and good engine oil.

regular oil should be replaced at 3500-4,ooomi. also replace the PCV every 20,ooomi..

[nicolef92]

Ok knew issue with truck .....its back firing ?? What causes this ?? Check engine light is on ...back fires at 1500 2000 rpm hiccups and falls on face and doesn't want to climb speed ??help !!!

[j cAT]

Originally Posted by nicolef92

Ok knew issue with truck .....its back firing ?? What causes this ?? Check engine light is on ...back fires at 1500 2000 rpm hiccups and falls on face and doesn't want to climb speed ??help !!!

what was the solution to the past issues. does it idle correctly now ?

with missfires at the higher RPM this may indicate bad plug wires and spark plugs. depending on your past issue/failure this may have cause plug fouling.

[nicolef92]

Truck is running like shit again ! Cleaned egr valve again didn't help this time ! someone help !!!

[spike1269]

I didnt have any of the smoke issues that I noticed.. however the truck was barley running so i was more concerned with idle issues. The plugs were carbon fouled so Im guessing would have been black smoke... My issue sounded like the motor was out of time, so I thought.. here it was the Crank position sensor, my idle straighten right out.

[spike1269]

Im having real close to the same issue.. I will try and clean my egr. but unplugging it dont seem to do it, and it isnt throwing a code for it.

[j cAT]

Originally Posted by spike1269

Im having real close to the same issue.. I will try and clean my egr. but unplugging it dont seem to do it, and it isnt throwing a code for it.

if the idle is only poor the egr sticking open at idle is possible.

unplugging will not do anything. what you would have to do is remove fromengine the egr. then making a plate with gasket cover the egr ports[ HOLES].

[spike1269]

Mine idles great..as it warms up the idle gets lower and lower, however still stays running.. The problem with mine is it runs great up to about 2000rpm then just falls on its face, and the hotter it gets the problem starts at 1500RPM instead of 2000.. no smoke but the truck will barely pull itself.Any ideas for that one??