Hello

I am trying to get to guidance and where should I start to look for my problem.
Problem:
when I am on the highway or cruising along the street, my truck has started to "diesel" during the midrange acceleration or cruising. Take off is fine and strong..but again it's the midrange performance that sucks. I just recently had to pass inspection so I have recently changed all of the components involved ( MAP, EGR, TPS, O2, new CAT CONVERT, fuel pressure reg., new wire/plugs, cap/rotor, Plenum gasket, TB gasket and a Thrustmaster muffler to boot). So I don't understand where the problem is coming from. I haven't put my Acton Code Scanner on their yet but will this weekend. I was just wanting to find a start point for this problem.


'Young Jedi Apprentice need guidance'

 

[updated:LAST EDITED ON 01-15-03 AT 03:53 PM (EST)]I assume by dieseling you mean pinging at midrange throttle. Have you had the injectors cleaned?
Could be a timing issue (over advanced) or even carbon build up. Try running some fuel system cleaner w/techron in it for a few tanks

Hope this helps

PS Check your plug wires and make sure that no 2 cylinder that fire consecutively are touching or not separated by an inch or so. you may be getting crossfire

Gasman
Do you have Gas?
Propane Execeptional Energy

 

ok..I have installed new wires ( AutoZone's Best)..since I didn't do that before..I put new plugs and returned the wires before. I don't have wire separators on the block so I have to figure (purchase) out something to help with separation. I have installed some injector cleaner yesterday and will see how that works. I may also replace the rotor again to see if that helps

Timing: I just moved the timing forward recently to see if that would help the problem, but it didn't. I think I may put it back to specs.

Injectors: I have not replaced the injectors since owning the truck and having the engine replaced. I have replaced the fuel pressure regulator.

Spark Plugs Testing: Is there a good way to check plugs while installed to see if a plug is bad? I have noticed on some of the new plugs installed it has some burning on the edges


Code Testing: KOEO - Code 11 / KOER - PASSED


Thanks for any assistance

 

Did you remove the "spout" connector when you changed the timing?
The only way I know to see how a plug is performing in use is a Sun Type scope.

Check your intial timing with the spout removed should be 10Deg BTDC
If not reset it. Then plug the spout back in and with the timing light still attached rev the engine to about 1800rpm and see how much it advances. Your distrubtor may be worn out and its over-advancing
Got a vacumn gauge? Check to see how much vacumn you have at idle and 1500rpm and if it is steady. You may have a leak causing a lean mixture at mid-range

Gasman
Do you have Gas?
Propane Execeptional Energy

 

>Did you remove the "spout" connector when you changed the
>timing?
Yes..I did remove the SPOUT

>The only way I know to see how a plug is performing in use
>is a Sun Type scope.
I don't have one of those !!! Sounds pricy !!!

>
>Check your intial timing with the spout removed should be
>10Deg BTDC
>If not reset it. Then plug the spout back in and with the
>timing light still attached rev the engine to about 1800rpm
>and see how much it advances. Your distrubtor may be worn
>out and its over-advancing

>Got a vacumn gauge?
No vacuum gauge...but guess I need to purchase one..I need to get some other gauges also the check pressure's

Check to see how much vacumn you have at
>idle and 1500rpm and if it is steady. You may have a leak
>causing a lean mixture at mid-range
>

Thanks !!!


>Gasman
>Do you have Gas?
>Propane Execeptional Energy