Laser rs gold package rough idle and hesitation.

[DaytonDsm]

Hello, I posted a threat earlier about this but didnt much of a helpful reply I read the vfaq and did all the trouble shooting and cleaning my TB but the problem still continues. What it is doing is that It will run for about 3 minutes but after those 3 minutes the idle will drop down to about 400 rpms and when I go to drive it, it hesitates and you can hear the rpms wanting to go up but it acts like its stuck at lets say 1k and once it finally gets pass that after working the throttle some it'll hesitate after 2k 2.3k 2.5k and so on. I've replaced the tps did the setting correct took off the TB and cleaned it very well. Someone said my timming didnt match with my tps which is making the ecu confused so it won't balance itself out. Could anyone give me a explanation about fixing this?

 

[Dhan]

I'm assuming you have a dohc 4G63 engine.

It sounds like an air/fuel mixture problem, or possibly the ecu is reading an incorrect a/f ratio and is trying to compensate for it. The latter can be caused by a bad sensor.
I just recently dealt with a no idle issue on my n/t. Despite the O2 sensor passing the tests illustrated in the shop manual, it was in fact faulty (due to contaminants). This probably isn't what's causing your issues though.

Have you done a basic visual inspection of your ecu?

 

[DaytonDsm]

No, I havent should I pull it out and give it a look over?

 

[Dhan]

You can't really tell much without hooking it up to an oscilloscope, but leaking capacitors and/or a slight scent of burn are tell-tale signs.

 

[DaytonDsm]

Could it be anything else, there is no engine light on or anything like that.

 

[DSM1G90]

wonder if your T-cable needs cleaning, or is getting hung up in the cruise control box (or, mechanism in the cruise control box is all bunged up in itself), which is mounted on the firewall....

..or, cable simply needs adjusting, being too tight and that you adjust that cable mount slider that is mounted on the intake manifold.. Cable itself needs about a quarter inch of slack between the adjuster and the connection to the throttle connection.

Check this first before messing with any of the other adjustment, esp the ISC, TPS, BISS and timing.

-DSM

 

[DaytonDsm]

Well, I thought of the same to. So when I took my throttle body off I looked at the cable and everything like that and it's all in working condition.

 

[Dhan]

Also, some other basic easy things to check is the spark plugs. The most recommended are NGK BPR6ES gapped to about .28. How do the spark plug wires look? Have they ever been replaced?

Sounds like basic easy stuff, but it's overlooked sometimes.


It still sounds to me like the ecu is confused about something after things get warmed up.

 

[DaytonDsm]

I haven't really thought of checking those small things yet I simply assumed with was the big things first. I'll give it a lookover tomarrow and letcha guys know.

 

[Dhan]

Sounds good

EDIT: I know it's a long shot, but if you have a spare n/t ecu to swap out for yours, that will help narrow things down as well.

 

[DSM1G90]

The most recommended are NGK BPR6ES gapped to about 0.28. How do the spark plug wires look? Have they ever been replaced?

He's an NT so he would need BPR6ES-11 gapped at .044 for if he went .028 he'd be snuffing out the spark on the plug.

 

[DaytonDsm]

Well, I'm gonna buy another TB and A ecu from the junk yard soon and see if that fixes the solution, friday I will be giving it a good tune up, wires, plugs, oil, filters I'll keep you updated.

 

[Dhan]

He's an NT so he would need BPR6ES-11 gapped at .044 for if he went .028 he'd be snuffing out the spark on the plug.

you are correct. Although I have my n/t's gapped at .039. Seems all right.

Well, I'm gonna buy another TB and A ecu from the junk yard soon and see if that fixes the solution, friday I will be giving it a good tune up, wires, plugs, oil, filters I'll keep you updated.

I'm not one to advocate buying replacement parts if I'm not certain they're faulty. Although n/t ecus aren't too spendy, and I suppose it's always good to have spare parts around.

Definitely keep us informed.

 

[DaytonDsm]

Well here what I am doing this weekend.
1. Leak down test of vaccum lines.
2. Trouble shooting Throttle body.
3. Trouble shooting ecu.
4. Plugs, wires, filters, gaskets.
5. Fuel filter.
6. Iacv and iac sensor.
7. all else fails i'ma urinate on it.