Engine/Transmission (1994 - 1998) stalling/slow idlewhen cold/hot ilde down inD

[mglaser]

Hi all

My sons 97 12 valve exhibits according to him some anoying symptoms:



Hard start? it seems to crank a little long then idles slowly at apx 4-5oo rpm

for a few mins. then idle goes up to apx 8oo this is a cold start symptom.



Stalling when engine cold mostly a sudden dip or let off of go pedal will cause this.



Hot idle down when in drive ie. 800 to 500 rpm brakes on at stop.



Seemingly slightly reduced power.

 

[KingS]

My dad's 97 is the same way but if left run when cold if you didn't plug it in it stalls and the take a long crank and some sputtering for it to start back up, We are still diagn. this problem we are just about to check fuel pressure to see if it isn't the lift pump ect.



As for stalling when you let off the pedal that is common if the engine is still to cold plus it takes more pedal to move the truck when the engine is still this cold.



As for idle if after the truck is warm and drove around and the idle is still this low it needs adjusted some that is all the information I can give hopefully someone else will post some more help.

 

[arthr31]

I can tell you that in very cold situations, when the truck isn't warm, when you let up the pedal to say "shift" the thing almost shuts down and comes back with a "ahreemph". This is normal in cold operation (for the last forever it's been -10 w/ windchill where i am, i hate it).



For starting, I'd recommend cycling the grid heaters 2to3x times, and lightly depressing the throttle to get the engine to catch right away when startup happens. Don't be hard on the throttle, that's too negative for the engine.



After warming up for a few to 10 minutes, drive easy until up to temp. Then, of course, drive like you stole it... :-laf :-laf

 

[Joe G.]

Setting the ilde up is pretty easy. The adjustment screw is on the back of the pump where the throttle lever is. You need a 10mm box end wrench. Loosen the lock nut. Easy the pressure on the screw by pulling the throttle linkage with your left hand. Turn the screw with your fingers. When you get it like you want it tighten the lock nut. 800 RPM in D with the AC on.



Letting the engine idle to warm up in cold weather is NOT a good idea. Maximum wear is when the engine is cold. So to keep it cold as long as possible let it idle. As soon as oil pressure is up, go. Take it easy until you see the temp gauge move. The engine needs some work in order to warm up. If you have an exhaust brake or a high idle so that EGT stays over 300° then idling is not so harmful.