K so i pulled these codes
10
111
311
332
411

Truck has no power whatsoever. Cant go up hills over 60 mph on highway in 4th.

also cylinder 1 is a black plug.

Please help guys i really need to figure this out.

 

111= system pass
311= thermactor air system inoperative
332= insufficient EGR flow detected
411= cannot control RPM during KOER low RPM check

Sounds like there may be a vacuum leak. Is the idle high?

 

idle is actually pretty low to normal i think. vacuum was like 18 when i tested it.

 

Not sure what's normal, but my 5L pulls a little over 20psi. I'd remove the EGR valve, inspect the Diaphragm for a rupture, clean the valve & mount portway. On the thermactors, hard to say w/o looking but they're a combination of electrical & vac in function. Dinky little plastic Vac lines.

 

hmm well we are pulling the intake manifold off this weekend i thing to see if i have a stuck open injector and it looks like the previous owner took it apart one time and used a make a gasket sealer on it. Im wondering if that has anything. Would a 2 or 3psi difference make that big of a difference though?

 

Gasket maker is not good for the intake manifold. Has the EGR and thermactor been bypassed?

 

thinks 18 its little low vacuum. but depends on idle rpm. the higher rpm at idle the lower the vaccum.my 93 v8 runs about 650-700 at idle and i get about 20 vacuum.
u want to keep it around 19-20 at low idle but if u can 21 vacuum ur engine its running great. and all depends on engine conditions.

 

tell me where to look and i will let you know. the PO did some wierd stuff so who knows.

 

dont have a tach so i dont know the rpm

 

I'm not sure where the control solenoids are on the 8, but on my 6 they're on the valve cover. See if they have the vacuum lines hooked to them and that the feed ones are getting vacuum.