rough idle in 350 while in gear

[7387chevynut]

Well I finally figured out my problem with the K5 blazer stalling out after it warmed up.............(timing was out of wack).

Now that....that problem is fixed, truck drives/runs fine.....accept for........the idle


When the truck is started up COLD........trans in gear/foot on brake........motor idles nice and smooth....


but as it WARMS up............the idle gets alittle rougher..........and once warm it will at times idle rough enough  that my Blazer at a stop, will shake alittle (annoying as fk)

dont know whats causing it........ my 95 chevy runs nice and smooth.........and my Blazer shouldnt be any different.

[RIP_K52007]

timing right on? still could be off a lil.

[Jjay78]

lil more info obout the blazer bud? fi? carbed?

[J.C.]

lil more info obout the blazer bud? fi? carbed?

90 tbi

[Jjay78]

what's your warm idol rpm?

[7387chevynut]

what's your warm idol rpm?

that i couldnt tell you, no TACH in my blazer.

it has me stumped................cause it idles so smooth when the motor is cold.........but when warm it will idle in gear/foot on brake.

[J.C.]

lock up converter staying locked up? or the electronic advance under the cap isnt working?

[MidMichiganMudRun]

stock build? or is there a Cam in it

[7387chevynut]

lock up converter staying locked up? or the electronic advance under the cap isnt working?

I wondered that too, about the converter........havent looked into it though.

stock build? or is there a Cam in it

Was told it was a newer 350 (which by the manifolds it has on it, it is, and as far as I know its stock.

[old school truck dude]

Cam, lifters, low oil pressure not keepin the lifters pumped up - oil gets thinner when warm, vacuum leak, egr maybe..

[Disturban]

Sticking egr valve very common problem on tbi motors.