New problem with car- mechanic doesnt know what it is

[sleep7]

Here is another problem. First, the car would not even start. Now, when your driving, the car seems to shut off. The RPMs drop to 0 and you can't accelerate. But the thing is, the engine is still running. When it happened to me I pumped the gas a little and it came back on again by itself. It first seemed to do it if either you got on it a little bit or if you stay at a constant speed for a while. Then the other day it shut off when it was idiling. So we brought it to a mechanic who also owns a SHO. He first bled the fuel pump.

That didnt work. Then he changed some wires around. That didnt work either. He said we should bring it to a mechanic who specializes in electrical stuff. If you know whats causing this, please chime in.
headbang

 

[revhardSHO]

May be the crank position sensor. I think SHOtimes has writeup on changing it.

 

[K-Dawg]

The first thing to do is read the codes. It sounds like it could be related to a failing Crank Positioning Sensor (CPS). If it is, you'll get a PIP failure code.

There is a section for this type of problem.

 

[ScotSHO]

First, what year/tranny SHO do you have? Smithsil is right on the crank sensor idea, typically this can be a problem with the symptoms you are describing.

You're check engine light should light up with crank position sensor problems. Pull your codes or find a new mechanic with half a brain to do it for you. Scary that your mechanic is a SHO owner and "changed some wires around". headbang

 

[Huntervf]

A mechanic who doesn't check for trouble codes?? shrug

I can almost guarantee it's a CPS. When you noticed the tach drop to 0 and you couldn't accelerate but "the engine was running", it actually wasn't running. The engine was still turning over though since you were rolling, and actually even if the engine had quit your tach would still register RPM's since the engine is turning over. However, since the CPS also operates your tach this that's a pretty clear symptom that your CPS is bad.

 

[SilverSHO]

Scary that your mechanic is a SHO owner and "changed some wires around".

1. Never let that mechanic near your SHO again.

2. See shotimes.com procedure on changing crank position sensor.

3. Change crank position sensor.

4. Enjoy.

 

[sleep7]

How much would it cost to change the CPS?

 

[SHOpride]

I picked one up at the discount auto parts store for around 30 bux.

 

[masho95]

sleep7:
Here is another problem. First, the car would not even start. Now, when your driving, the car seems to shut off. The RPMs drop to 0 and you can't accelerate. But the thing is, the engine is still running.

Usually a hard start is related to the CMP (Camshaft Position Sensor) not the CKP (Crankshaft Position Sensor). CMP is especially suspect if the tach drops to zero while the car is still running, the CMP sensor drives the tach signal. Start by pulling the codes yourself, you can save yourself a lot of diagnosis money. Check out the following links for pulling the codes yourself:
http://dalidesign.com/hbook/eectest.html
http://www.midwestsho.com