Admiral Blue

My car hesitates and surges at VERY low speeds. I'm talking about when I come to a stop from 3-4 mph to 0, it jerks a little bit, as it does when I let off the brake from a complete stop and idle away without pressing the gas. It seems to be decent at WOT...no misfires and maybe just a little loss of power. Once in a great while it will be slow to downshift, but that's about it.

When slowing down as described above, it does not hesitate with the car in neutral...only when in gear. It idles very rough.

After taking my car to two different people (both excellent mechanics), they are both about 99% sure it's the opti. We changed the plugs, but there is always that 1% that it won't be the opti with my luck. :smash:

Also, one noticed a "gurgle" in the exhaust when decelerating which he seemed to think pointed to the opti. Both mechanics don't think it can be as simple as wires.

Anyone have similar symptoms? I'm taking it in later this week to be fixed, but I wonder if other cars experienced this.

:confused: :confused:

Thanks!!!

STL94LT1

My 94 had the same symptoms, and they get worse with time.

vader86

id check the IAC and the TPS, if neither of those have any problems, its the opti.

bogus

yup. about sums it up.

the real dead give-a-way symptom is a lower redline. the spark cannot fire weill enough and it will start to miss.

it will show a code 16 on the SES also...

Danger Dave

Jeff,
Mine had similar problems and it ended up being a cracked opti and PCM. Good luck with it, I bought my opti through Jeff Kopp Superior Chevrolet for a good price.

Admiral Blue

Thanks for the replies, guys.

STL94LT1 - How long did it take yours to get worse? I was hoping mine would, but it really hasn't gotten too much worse. It's been doing this for about 3 months and about 5000 miles.

Vader - As far as I know, the TPS and IAC were checked, but I will have them looked at again. I was hoping it would be the IAC. :yesnod:

Dave & Bogus - Thanks for the advice...I think a scantool did pick up a code 16. No misses at high RPMs though.

GlockLT4

The sign of my opti going out was a nice "pop-corn popping" sound under the hood above 2500rpm or so... not a good sound :eek: :eek:

rcdk

I don't know, mine has the exact same symptoms right through an opti change.

And I did have an opti problem because the water pump would leak on it when it got hot. As soon as my car warmed up, it ran like a dog. No misses, just no power. New pump and opti fixed that, but I still have a huge hole in my torque curve below 2000 RPM and a slightly rough idle.

I replaced the IAC as well.

Fabio7

It is the opticrap. The first time I changed it the vette was just like yours.

kkonen

Watch out for the results of a bad opti. Mine went bad about 2 months ago. The warranty covered it. However, the mechanic said that my wires were bad, so I am in the process of changing those. The bad opti also fouled all my almost new spark plugs, so I got to change those. Now my SES light comes on, a quick code scan shows that my O2 sensor is not working properly. It is probably fouled also. My car is bleeding my patience and wallet dry.

STL94LT1

My opti progressively got worse over about a years time. During this time the car was driven less than 2000 miles. Also, the opti would go for periods of time and operate perfectly. But finally it just gave out.


[Modified by STL94LT1, 2:11 AM 6/11/2002]

Admiral Blue

That's good to know, STL.


Sounds like it's the Opti. Now I'll worry about the other stuff you guys mentioned as well. :cry :crazy: :)

Thanks for all the advice! :seeya


Jeff

LT4POWR

In addition to the spark plugs and O2 sensors, when mine died it also killed a head gasket. :mad :mad :mad

John Row

Find a shop with a TECH II (I really want one of these things) and have them run the tests. Any good Chevy shop should have one. It may not tell you the Opti is bad, but you could eliminate just about every thing else.

Pay them for an hours diagnosis. They might find something simple (but don't hold your breath).

Good Luck.

Admiral Blue

Thanks John. Already did the diagnostic a month ago...they were almost certain it was the opti. Well, just got it back today. Still the same old problem. See my recent topic. :(

ColinOpseth

is your car an automatic? could it possibly be the Torque Converter Lockup Solenoid not disengaging until almost at 0mph? :)