Rough Idle 1990 5.7
#1
Rough Idle 1990 5.7
I have a full size 90 with the 5.7. I have had problems with rough idle while in gear. I had a friend check the timing and it was set at 6 so he put it back to 0. That worked for about two week till I replaced the battery. I checked the idle and in park its about 550. I checked for any vac leaks and found none, any ideas????
#2
Have you cleaned or replaced the EGR valve? When was the last tune-up? A sticking pintle valve in the EGR valve or worn spark plugs/wires/cap/rotor could cause that.
Josh Hucks
Josh Hucks
#3
EGR has not been cleaned or replaced. Last tune up was july 08 plugs/wires/cap/rotor/fuel filter. EGR looks to be factory org. itsgot 104k on the the org. motor
#4
Have you checked or replaced the throttle body base gasket? These are known to leak causing a vacuum leak that is very hard to find.
How does the fuel spray out of the injectors look?
How does the fuel spray out of the injectors look?
#5
Clean the throttle body and Idle Air Control. You are running AC Delco spark plugs right? I would also re-check the cap, rotor and wires... take a look at the plugs for any weird color or signs of fouling.
#6
I am running ac deco plugs and injector spray looks good. Will look over the other things noted. Thanks for the help. Will keep post up to date.
#7
I found 1 of my plug wires has been melted a little. It doesnt look to bad but could this be a problem? It now has a bad vibration at hwy speeds. I dont dare do above 65mph
#8
If you suspect the wires being a problem, mist them down at night with the engine running with as little ambient light as possible. If you see arching from the wires, they need to be replaced.
#9
#10
Problems solved
Wires were bad and U Joint was bad
Thanks for the help
Wires were bad and U Joint was bad
Thanks for the help