BigNNasty

Ok, so after reading about it, why would it do at just that range of RPMs his has? To me, if the TPS is broke, it's broke. It wont be a hit or miss deal. This is what he's experiencing is hit or miss. Although, Clarks-garage does list symptoms of a broken one, and he has some of them. Then again, I think he's got something in the fuel system that might be clogged, or just in need of cleaning badly. He said it doesn't do it all the time, and if the TPS was broke, you'd think it would do it everytime.

Does the car idle weird? Start up fine? Will the car cut out if you have it out of gear and rev it up to 4k?

Like I said, our Chevy II it would sometimes idle fine in Park, but as soon as you put it under a load, it would cut out. I doubt its your fuel pump at all, because thats the first thing we replaced on the Chevy II, and that didn't do jack. I'd just hate to think your gas tank was f'ed. I've never heard of anyone having problems with their gas tanks, but you never know. Man, it's so much easier to work on a carb'ed car then all this fuel injection!!!

95Juan

nope, car idles perfectly. every now and then it idles high (REALLY rare), and the exhaust backfires (when i say back fire, i mean fire shoots out the exhaust) when i let off the throttle or shift a lot more than it does otherwise (i'm assuming overly rich for a bit?)

hahahahah, the car will not cut out when it's not under load, which is why i thought fuel problem. if i'm sitting at a red light, i can blip the throttle at 5-6k all day long and not have a problem. (note- i've never done that )

BigNNasty

I have no clue then...

I think it's safe to rule out the fuel pump (if your fuel pumps trash, it wouldn't do it very seldom like it does, it would have to do it more occasionally).

Also...I'd say the TPS. Mainly, I say it because like I stated earlier, it's either broke or not, there's no middle road on that kind of thing, you know? BUTTTT...It doesn't hurt to take the time to check it!

I'd say definetly something with your fuel system. Even more so, whats regulating how much fuel your motor gets. Being in R/C and around Nitro engines, you learn what being to rich/lean does to a motor very fast, as thats mainly how we increase our power is leaning the motor out. With Nitro Engines, if you run to rich you produce TONS of exhaust smoke. Now, if you run lean you have hardly any exhaust smoke, but, it also increases your idle because your motor is obviously revving higher then if it were being run rich. So, if your idle is shooting up SOMETIMES, your motor isn't running rich (being starved of fuel/leaning out), so when it does idle high or cut out, it's not recieving the correct amount of fuel.

I'm betting money on the FPR...

hosrom_951

I had that similar problem last winter, it turned out to be a bad coil.

Well, the coil was good (in voltage), but there was green electrical corrosion inside the coil. Replaced it and problem free.......at least for that part

95Juan

let's get a pool going.

(well, an imaginary pool, i dont have money to be throwing at you goddamned RL monkeys)

1. TPS

2. FPR

3. Coil

4. A gremlin.

hosrom_951

Juan,
the TPS and coil are simple to test, follow Clark's garage procedure.

As for the FPR, i really doubt it, but who knows.

As for the gremlin......why couldn't it be a leprecon?

95Juan

i'll try that once i get everything else sorted out.

does anyone know of anything that could go terribly wrong if i let this go?

what happens if you just disconnect the TPS?

austin944

Under boost, the ignition system has to work harder to make the spark jump the gap. A marginal ignition system might cause the problems you describe.

If it were a fuel-related problem, I don't think you'd see the car shut down completely and suddenly like you've been experiencing, it would be more gradual (unless none of the injectors were firing).

If the fuel pump stopped running or the fuel delivery failed, the residual fuel pressure in the fuel rail would still allow the engine to run for a very short while before shutting down, but run in a very crappy way.

So I would check the rotor/cap, check the coil and coil wire, and perhaps the plugs and plug wires, and battery connections/voltage.

95Juan

yeah......like i said, imagine hitting the rev limiter mid-way through the RPM range.

come to think of it, it only happens in 1st.

goddammit....now there's more things to check. ignition should be fine, it's been through several "and while you're doing that, check if there's anything else wrong with it" inspections by my mechanic, and he never misses an opportunity to take my money.

BigNNasty

haha

Just hang in there...you'll get it all sorted out here soon!

and remember...

"The Juice is Worth the Squeeze!"

testarossa_td

It fails the same way the AFM track does, and thermal expansion can play a key part as well as they way you come on to throttle...hit the accelerator and you might jump past the bad part of the track.

http://www.frwilk.com/944dme/afm.htm

austin944

I'm trying to imagine what that's like since I've never hit the rev limiter in my car (I am a puss). If the engine still runs but runs crappy then it could be fuel-related.

For the ignition inspection, you can try substituting when was the last time any of the plugs/wires/rotor/cap/battery were replaced or looked at by your mechanic.

Andial951

it could be a duende