[MWebber]

well, I've racked my brain trying to figure out why my car is being such a pain in the butt....

it idles high(900-1000RPM) and with a studder every 0.5 to 2 seconds randomly.

I checked my plugs(NGKs) 3 weeks ago, and although they looked used they looked fine. I checked them again over the weekend and they look like I took the cake frosting to them, filed everything to a 45 degree angle, refrosted, and regapped them to 0.5 inches. needless to say there's now new plugs(Denso) in the car. so why now is the car running lean?

The TPS I checked, 3 times, I have a spare TPS, it checked fine (and exactly the same as the first TPS) and is installed on the car for giggles.


The ISC was checked, all three of the ones I have, they all seem fine.

new cap and rotor, wires are almost brand new(toyota)

I've been over the vacume system 3-4 times and can't find any leaks. new lines ~1 year ago.

O2 Sensor is less than 1 month old.

the timing is set to something rediculous because at 10 - 14 degrees the engine chokes, hesitates, and has No power. (distributor 1 tooth off?) I "Know" the timing belt is right.

Injectors I haven't fooled with yet. Check connector doesn't work.


I'm sure I've forgotten some things I've already tried, but please, throw all the ideas to guys can think of.

TIA,
Mike

 

[Flyin' Hawaiian]

okay Mike, I'll take a wsing at it!
You say the check connector doesn't work, do you know why? The reason why I ask this is that the check light will not function if your tps is set incorrectly.
I had the same problem with the slight stutter at idle and the lean running. I tried to use a multi meter to set the tps, but found that it still wasn't quite right.
One way to tel if the tps is not set axactly right(it really is sensitive, just breathe on it while tightening the set screws and it'll be off!!!!) is to drive the car in first gear(or 1 if auto), bring it up to about 2000rpm and s l o w l y back off the throttle. If it drops off like you turned the key off and stutters if you give it a little more throttle, your tps is still off.
You'll probably find that once the tps is set correctly, your check connector will probably start working again!
As for the lean condition, you can always compensate for that by modding the maf, but if it's that lean, I'm thinking you have a fuel delivery problem, maybe clogged fuel filter or a bad O2 sensor. Try getting that check connector working so you can pull the codes before going any further, as it'll probably tell you what to work on next with your fuel problem.
Good luck and let us know whatcha find!!!

Chris

 

[MWebber]

Thanks for the tips Chris. as soon as I get moved to the new house and have all these wisdom teeth cut out (this friday it all happens :shock: :roll: )
I'll pull out the gear from boxes and have at it all.

did I stump everyone else? any more ideas?

Mike

 

[Supra Bob]

Have you chgecked the AFM for the lean issue? If your AFM is not working right, it could be telling the ECu that your getting less air than you really are, in which case that would also account for the lean condition... Also, like Chris said, check your Injectors to make sure they aren't clogged or possibly the filter could be clogged, leading to fuel starvation....

 

[Racetek82]

don't forget to check the coolant temp sensor, it plays a big part in the fueling calculations.

 

[Supra Bob]

Ray... care to expand on that idea? To my knowledge, the temp sensor will make you only go Rich, not lean.

 

[Racetek82]

haha...okay Bob..i think you caught me in my moment of absent mindedness....I was thinkin about richness, not a lean condition..lolz. Thanx for catching that.

I would also say check out the AFM, it also includes an air temp sensor...which might affect things here. Timing issues seem to be exhausted, but you may wanna check out if your crank keyway may be worn out? just a thought. Lemme ponder this one a while..eheheh

 

[Supra Bob]

LOL... its cool... I hoping for a new bit of info cuz I had never heard of that before... Oh well

 

[GreyFalcon]

After you have checked all of the above, check the EGR system. I think you have a combination of things going on that may be causing the idling problem. Once you determine that your throttle position sensor, and oxygen sensor are working correctly, look at EGR. The passage runs across the top of the intake plenum, and likes to block up where it turns down over the middle of the throttle body. Mine was blocked, and it really tore up my plugs (test the EGR valve, modulator, the VSV switching valve and the BVSV on the thermostat housing) . I thought it was a lean condition, but apparently EGR cools the fuel charge somewhat. My plugs look a lot better now. As for your timing, if your harmonic balancer has slipped, you can't use a light to get an accurate timing, but a vacuum gage attached to the intake plenum (where the hose goes to the power steering pump) will do a good job. I advanced mine to where the vacuum just reaches the highest value, and it runs beautifully. When was your timing belt replaced last? Good luck.

 

[MWebber]

Thanks everyone for the comments.

The timing belt was changed right after the old one broke :shock: I'm sure the timing belt is right. at most I'm about a 1/4 cog off on the exhaust, but to be totally anal about that, I'll have to get some adjustable cam gears.

Like I said, I'm having oral surgery tomorrow (Friday) to have 3 wisdom teeth cut out and 2 others pulled. we close ont he house tomorrow too... :shock: I'm going to be down and out for a few days, but once all this get's settled, I'm planning on taking a whole weekend to figure out the problem with the car once and for all or just Norbiefy the darn thing.

thanks again everyone,