Over the last several months I've asked this a few times and have been slowly [in spare time from work and school] narrowing it down.

A breif over veiw [since I've posted it before] car hits a 'rev limiter' at high RPM- normally right around 5000-5500. The only other time it does it is if I get on it hard in low RPM. Ex: 4th gear, 30mph, 2000RPM it will hit the 'fuel cut / rev limiter'. This is a 5AT.

Here is where the plot thickens. If It hits the limiter I immeditately get off the throttle and shift. Sometimes when I go to even lightly get back on the pedal it will get the hesitation again and I have to back off and wait like 3 or 4 seconds and get push the gas pedal to get up to speed.

The SLIP light comes on, the CEL comes and the VDC won't turn on [VDC is always off, so if I push the button again the light won't go away].

I am throwing a code for Crankshaft Position Sensor, so I know I need to look into this [possibly sheilded?] My question now is, how is the SLIP light connected? I know its NOT loosing traction at 2000RPM and 40%-50% throttle. The hesitation is similar to what others describe, its violent, and can't be good...

I have the UTEC and want to datalog it and post it... but don't know how to go about doing that. Tried to follow the directions, but I'm to poosy afraid I'll mess my tune up. [unless someone wants to PM me even better instructions then what I got off TurboXS website.]

Thanks!

 

I had what I believe to be a very similar problem with an APS TT and unichip. My shop spent a couple weeks trying to figure it out.

I really do not know enough to articulate the problem, but here was the explanation of the problem given to me by my shop (quote from email):

This problem had us baffled for weeks and we are still not sure exactly WHY this caused the problem, but it did.

I hope that helps.

 

My first guess [ you get a crankshaft position sensor code ] is your wiring is f-cked up . Or there is a issue with the Utec .

Dont know your motor history...is it built with cams ?

 

That was the first guess with mine as well... two crank angle sensors later, and after checking all the wiring and replacing the wiring harness, the problem was still there.

 

I had a similar symptom, but mine was an igition coil issue. do you have stock ignition system?

 

The ONLY things done to the car are:

ProCharger, 7psi
UTEC [problem happened with GReddy EU also]
750cc RC Inj.
Walbro 255
SGP Return fuel syst.
Fully upgraded tranny and rearend

Why the huge injectors I don't know. They said I maxed out 380, then the 440s, so they put 750 in and said I'll never have that problem again [I would think!!!!]... those don't seem to be an issue, car idles pretty descent and on decel it gets alittle rich, but other then that they seem just fine.

So far to check off is the fuel pressure, Crank Sensor to see if those fix anything. [I'm thinkin maybe the large injectors were because the pressure is lower then normal?]

But any reason why the SLIP is comming up also?

 

I don't think utec can manage that big of an injector. you have no reason to be running that at 7psi/low hp, anyways.

 

Again, thank you.

But what about the SLIP light. Thanks.
I've posted about this 4 times over the last few months... I've heard about the injectors 4 times...

 

Did you have problems as soon as you put on the SC ? Or the Utec ? Or some other mod ? I would think you got something outta wack if it did it with the E-manage and the Utec . Some wires or some thing

 

When I had the problem, the SLIP, CEL and VDC lights all went on as soon as the hesitation hit. Since the "fix," none of the lights have come back.

See my post above.

 

So you suggest checking the fuel maps? Can you PM the name of the shop that worked with you along with what computer you are using?

 

I think i replyed to one of your old post. I had the exact same issue and what is happening is when you get that violent hesitation it is because the utec is going from a say 7psi fuel load site to a 20psi load site because of a software error which in turn dumps a ton of fuel and boggs it out. I confirmed this with my tuner while doing a street tune, so it is def. an error with the utec. I upgraded my software to v2.8 and havent had a problem since.

 

Ah, you just upgraded and didn't have to send it back?

 

+1 all my lights lit up like a christmas tree.

 

Yep, just upgraded software. Nothing else.

 

You can always replace the crank angle sensor first. It's only $50 at the dealer. Then it's 1 bolt 10mm and a plug. If you can change your oil you can replace this part.

 

You have a PM