Hey guys new to the forum..i have a 95' 4.9L..i recently changed the spark plugs n wires on my truck n it was sounding like it was miss firing just at idle.it drives perfectly fine just idle rumbles the motor.so i thought the cap n rotor would help so i went out and got a new one but still the same thing..and help here>?

-ive checkd to make sure the wires were on right at least 15 times..(1-5-3-6-2-4 clockwise)

 

Vacuum Leak (at intake manifold or throttle body?)

EGR Valve (leaking?)

PCV Valve (plugged?)

Air Filter (plugged?)

Weak Battery(?)
A weak battery caused my 87 4.9L EFI to idle rough and go dead at stop signs.
I charged my battery and when it idled normally and didn't choke down at stop signs,
I replaced the battery and I've had no more problems with it idling rough.

FYI - An alternator will work overtime trying to charge a battery with a bad-cell
and will burn itself out prematurely.

 

if it was my battery wouldnt my lights dim at idle?cause they dont all lights are nice n bright!

ill check those other sympthoms out too

 

ok so i just ran my check engine light and iam gettin code 327...any ideas on how to fix this problem?

 

That's EGR related... things to check (with engine warm):

vacuum - pull the vac line off the EGR and see if you get vacuum as you increase the throttle.

If no vacuum - check EGR solenoid (on driver's side valve cover) for vacuum going in. If vacuum is going in, could be issue with either electrical wiring or a bad solenoid.

If you get vacuum, check for EGR movement - there should be little holes around the bottom of your EGR valve that you can see into. As rpm increases, you should see the little diaphragm raise inside there.

If you are getting vacuum and valve movement, the issue could be the EVP sensor (where the wiring plugs in on the top of the EGR valve).

Good luck -- this one sometimes ends up being a real adventure!

 

deff sounds like an adventure..will have to do all this on my next day off thanks for all that info


can the egr problem be the reason why my motor sounds like it misses/rumbles at idle?

 

Sure could - it'll act like a new one after you get it all sorted out.

 

you said before check the egr solenoid on the driver side valve cover i have a straight 6 were would it be located on that?

 

This diagram is about the best I could do... If this doesn't get you there, just follow the vac line from the top of the EGR valve - it'll lead you right to the solenoid.

 

^^^thanks