Hesistation @ 2k in 2nd gear

[WolfpackTLC]

Just like the title says.... I did the Seafoam treatment, changed my plugs, and now I have a hesitation from 1900 rpm to around 2200 rpm... but ONLY in 2nd gear, or in neutral. I'm guessing that's the critical engine load for my problem. It's not the wires, otherwise I'd guess it'd do that all the time. The plugs are new, and gapped and torqued to spec... the cap and rotor look good, and all the connections are kosher. Any ideas?

It's a 95 w/ the TRD S/C and 195k.

Wolf

 

[WolfpackTLC]

17 people look, and nobody has any suggestions?

 

[clownmidget]

ok, so I'll bite.
1) What's your timing set at? Maybe advance a bit to see how she reacts.
b) Bypass valve on s/c moving properly, not hanging up on hose clamps?
3) How's your fuel delivery? Condition/age of fuel filter, fuel pressure regulator, any signs of starving (ie, high end lean, pinging, etc)
d) Vacuum lines all in order? Check them for splits, routing, etc. The s/c puts these in some susceptible places depending on who did your install.
5) throttle cable moving smoothly, no kinks, hangups, etc. Also, is TPS properly fxning? A few folks have had these out of adjustment or not working properly.

If it's doing it in neutral then it doesn't sound like it's load induced. I suspect a vacuum problem if it came on suddenly.
Good luck and post your solution, please.
Mike R.

 

[cruiserdan]

Engine torquing over and moving crispy wires by the EGR valve?

 

[IdahoDoug]

Clarify something. I get the impression from the post that this started AFTER you'd replaced a couple things and/or done the SeaFoam thing?? True/false?

DougM

 

[WolfpackTLC]

Yup.

It started AFTER 2 Seafoam treatments, and AFTER new plugs were installed. Timing is set @ factory recommended specs w/ the S/C.

I've checked ALL the obvious hoses... anybody know of any one's I may have missed?

Dan-

I'm not putting the engine under much stress, so I don't see it torqueing over THAT much... but I could be wrong.

I was unaware that there was a S/C bypass... I'll have to look at that...

Fuel delivery is good... I'm just guessing, b/c otherwise, I'd have OTHER problems... and fuel delivery isn't usually limited to just a particular load range and/or RPM.

This DEFINITELY isn't a throttle cable thing... If I try hard enough, I can get it to do it higher up in the rpm range... it's almost like the plug wires may have something up, but they're only 1 year old.

Anybody else (thanks you guys...) ?

 

[robbie]

*May want to by pass the two speed relay for the fuel pump and see if this helps. It is on the driver's side in the engine bay on the fender area. Check your FSM to see what pins to jump to get full voltage to the fuel pump. Have the injectors ever been cleaned out of the truck? Has the fuel pump ever been replaced? any one of these things will create problems of different sorts for you. later robbie

 

[WolfpackTLC]

Hmm... anybody else?

 

[concretejungle]

i think maybe it's the supercharger. You should remove it and give it to me.

 

[waskillywabbit]

Spark plugs

J,

I think you put the spark plugs in upside down!

 

[WolfpackTLC]

UPDATE:

Ok, so now it only SLIGHTLY does it... hmph... any ideas?

I have changed NOTHING since my last problem.

 

[warpdriv]

I was talking to a person that works on my 80 and he has a friend that had a loss of power. After plugging it into the computer, it showed the fuel pump was not working to full capcity. It may not be a fuel pump, but you might want consider going to a shop to have all the electronics analyzed.

HTH,

 

[WolfpackTLC]

Nah... I think fuel pump would affect the entire power band, not just this area...

It's not as bad as it was... maybe the plugs? Come on.... somebody?

 

[ppc]

The ECU controls the fuel pump relay only supplies full voltage at startup and under moderate to heavy load. Like Robbie suggested remove the fuel pump relay and wire the pump for full voltage. Even with a weak pump you will be amazed by the results. It's a one banana job. Other thing is a faulty fuel pressure regulator. At your mileage I would replace both regulator and pump and check the vacuum line to the regulator.

 

[WolfpackTLC]

Ok... Ready to try this.... it's a one banana job? Where is it, and what pins do I jump?

(awaiting my banana)

Wolfpack

 

[Safado]

Wolf....

What does your Air-Fuel Ratio meter do when this happens? Does it bounce back and forth between Rich and Lean?

 

[concretejungle]

J, is it still doing the hesitation thing? What about your other posts about getting the dizzy wet going through a mud hole this weekend? Was it still hesitating at Uwharrie this weekend? I still think something is wet. Mine had a hesitation at about 2k rpms after it got really wet. I opened the hood, let it air dry all day in the sun taking the plug covers off. That basically fixed the problem.

Just guessing.

 

[WolfpackTLC]

No A/F meter here Safado....just an EGT and a Voltmeter...

But if you've got a " real time " A/F meter, it's gonna bounce back and forth no matter what you do... should only be still @ idle...

Concrete-

Nothing is wet.. I unplugged EVERYTHING and dried it all out. I also fixed my no start problem....

I had the hesistation BEFORE Uhwarrie... it's still there now... just looking for suggestions.

J

 

[Scamper]

I second the fuel delivery system. Test the relay as Phil mentioned. He posted on this about a year ago--sent me the EWD for it too and indicated which pins needed to be jumped. It's a real easy test--the hard part is finding that relay which is well hidden inside a hole in the DS fender right behind the ABS (assuming your truck has ABS).

If that's not the ticket, then I'd move on to Clownmidget's thought concerning the bypass valve. With all you mud wrestling, you may have gotten some muck in it that has been preventing it from opening/closing at the appropriate times.

Do you have a scanner? If so, try to see if it's running rich or lean during the time it's hesitating. That might help to figure out where the problem's coming from. [Nevermind...just noticed you had a '95].

 

[WolfpackTLC]

Ok... got the bypass done...

For those that are interested... it's the red/green jumped to the red/black wire... it's hiding in a hole in the DS fender...

Christo and Ben were kind enough to help me figure it out, although they had to bicker about what color was what... ONE of them is color blind... ha ha ha.

The bypass helped... SOME... the hesistation is much more subdued now...

I'm thinking I might need new wires, although they're barely 30k old... anybody know where I can buy just the snap on connector thingy for the wire-to-cap contacts? I broke one of those today.

Plugs didn't look bad... just soaked in gas from the aforementioned starting troubles.