Hesitation/bogging/rough idle in 89
 

Just replaced the injectors....egr cleaned. Everything back together nicely. It was running like crap prior. Seems to have more power...but serious hesitation when stepping on the gas (especially under load)...some popping. Any ideas? Suggestions?

Thanks!

Checking/pulling "stored" ECM codes is pretty easy and a good place to start.

:thumbs:

Do a fuel pressure test.

if there was a trouble code...wouldnt the "check engine" light remain on?

Depends on the "trouble" but not always.

:thumbs:

New injectors not seated fully?

:iagree:

Good place to start.

they seem to be seated....but how can I really tell? I mean, the rails are all bolted down, etc.

cant tell NOW but when they go in, make sure they snap top and bottom positively, also, make sure the old orings come off, they will fit in with two orings (by mistake) on top of bottom,and they wonr really leak enough to tell.

So I can move them up and down slightly...should they be seated to the block as much as possible? (feel kinda stupid...just have never messed with injectors)

with them installed and the ruel rail tight, they should barely move (twist left or right) zero up and down.

Have you disconnected your battery after replacing the injectors?

it was disconnected while I replaced them...but not since. ????

new injectors
 

remove negative battery cable , and turn headlight switch on TO COMPLETELY DRAIN ANY RESIDUAL VOLTAGE FROM THE ELECTRICAL SYSTEM ,ecm and radio capacitors can carry enough residual voltage to NOT CLEAR ALL THE CODES , I just did my injectors today and it WORKED FOR ME :steering::auto:

So I finally changed the S.O.B. fuel filter....and cleared the codes. And no "check engine" came on. Seems to run a little better...except for that hesitation/bogging when you put your foot into it... starting to kinda piss me off!

Did you check the fuel pressure? I did my injectors and then a couple weeks later the fuel pump crapped out. It can be tricky, my pump would work ok when it was cold but once it warmed up a little forget about it.

It's the other way...when it is cold it runs like crap (bogging when you stomp on it...rough idle). What is weird: so it's running/idle rough...I disconnect the MASS AIR plug sensor plug...it seemed to run better. ???? Any ideas?

Thank You Everyone!
 

Thanks to everyone for all of the suggestions!

Did you get this figured out? If it runs better with the MAF unplugged, I would think that it is sending bad info to the ECM. Had similar situation with mine and went away with a new MAF.