HELP! misdiagnosed bad opti now ~$6200 in repairs??
 

Okay, I need help with this, or I'm losing my car and a considerable chunk of change. I have a 97 Z28 M6 with 116k mi. I'm outside of Houston, in Kemah, TX. It's pretty close to stock, but you have the important info. a couple of weeks ago, I got a p0300 (random misfire) code on my car, with no other indications except that at just a few random times over the past few months, I would notice a rough start in the morning. single code, dunno if it was repeated annunciations because the autozone guy didn't tell me. I figured it was the plugs and wires since I've never had them replaced.
I took it into a local shop that I thought I could trust, and they told me that the detail showed it was having random misfires on cyl 3, 5, and 7. Theyy said that after looking into it. the water pump seal had leaked all over the opti and ruined it. I figured this was at least possible, even though I had ZERO indications of low coolant or leaks or anything else. Cost to repair? $1800. That sounded high, but I haven't had to do anything to my car in about 16 months, so I was grudgingly okay with it. to try to save costs (on labor, really), I asked them to go ahead and do the plugs and wires while they're in there, and that was $1100 extra. again, this sounded high, but I've heard quotes from $700-900 for years on doing the plugs and wires because the LT1 is such a PITA.
Total damage =$2900, which is okay if I go another year without a problem. while they did those other things, they decarbonized the intake using high pressure Motorvac.

when I got the car back, it stumbled on acceleration a couple of times as I was putting it through its paces on the drive home. That was new, but I figured it was something about the computer re-adjusting to the new ignition.

The next morning, a minute or so after startup, the coolant light came on. I stopped the car, checked the overflow bottle, and it was almost dry. The dipstick was damp, and only the very last notch was wetted. definitely not filled as it should have been. tried to get the rad cap off, but it was tight on there. at most, I loosened and retightened it. other than these things, I was nothing. no leaks. there was a coolant smell, but that's to be expected if they just refilled the system after a water pump replacement.

I called and asked about it and the shop guy said that it was probably just a vacuum in the system that kept it from getting topped off when they were prepping it for return after the repair. I've heard that this could happen before, but it always makes me think that the shop is sloppy in their QC.
The shop guy told me to bring it in and they would top it off. This was two Fridays ago. I waited over the weekend to bring it in when I was heading into work, and when I started it up on Monday, waited a couple of minutes to look for the coolant indicator. It never came up, but while I was waiting, the SES light came on again. Alarming. I stopped at Autozone to have the code checked and it came up P0300 again. I took it back to the shop and told them about it. they sat on it for nearly 3 days, and told me they had two people looking into it (when I picked it up, the radio security code had not been locked out, telling me they didn't do anything requiring disconnecting power) and then called me up and claimed that they would START by checking/changing the head gaskets. Cost? $3300. And that was it. they weren't looking other places, and weren't admitting to any wrongdoing. they misdiagnosed it from the beginning, and were using my wallet to experiment.

The total at this point would have been $6200, and my car is old enough that I worried about anything else going wrong in the next year. that would break my budget by a longshot for maintenance. as it is, the $6200 breaks the budget, but I'm left with an impaired vehicle.

I took it to another shop, and told them my problem. note that when I drove it from one shop to the other (at least 20 minutes of drive time, with a cold start in the morning), the SES light DIDN'T come on. ???

the new shop started it up the same day and said it seemed just fine. they let it sit overnight and did a cold start in the morning this past Friday and said it ran rough for a few seconds or so, and then I guess they got the light. said they found additional codes (crank position along with the misfire codes). They did an emissions probe and said they didn't get coolant readings in the exhaust. they did another test and said that they were getting just the slightest readings for moisture in the cylinders, indicating that there is either an intake manifold coolant leak or a head gasket leak. they can't isolate further. cost for the intake seal? $700. cost for the head gasket? $2200 ($1100...50% less than the other shop). Now, since the other shop already took me for a ride, and I have no way to prove it and get that money back, I'm basically faced with spending good money after bad.....OR getting rid of my car.

I don't want to get rid of my car, but my wife is indifferent. If the intake seal is the problem, I suspect that it was damaged during the MotorVac test. but $700 would at least delay having to sell it.

Can anyone tell me, based on this lengthy tale, whether or not this is a likely suspect? could sloppy work have allowed something to leak into the intake when they changed out the water pump and opti?

need a story by tomorrow, if possible.

THANKS!!!!!

Brian
6spd4lf
1997 z28 6sp, !CAGS, 3in SLP exhaust, gutted MAF, K&N, 52mm tb, SS rims (285/40 17)

What did you do to gut your MAF sensor alot of times people will have problems with them like what your describing after tampering with them.

If these are the best shops in your area, then you need to either learn to work on your own car or sell it.

At the very least you need to learn enough about your car to not get raped so badly.

Replacing an optispark that may not be bad?... $1800

Plugs and wire replacement "to save costs"?... $1100

Fixing an LT1 coolant leak by re-sealing the intake manifold?... priceless.

how about actually telling me something constructive?
do you typically figure out EXACTLY what the problem is before taking it in for work? or do you just (miraculously) have shops in your area that are always completely

there was no indication of a coolant leak before shop#1 had it. no low coolant light, no smell of coolant from the front end. But I couldn't say they were lying because I didn't see it. the only indications I have ever seen are the random misfire on multiple cylinders code. there was no indication of a coolant leak after I got it back from shop#1. just that they screwed it up and didn't QC it when they were "through". shop#2 is telling me that they actually did probe tests and they're finding trace amounts of coolant in the cylinders. there are no leaks external to the motor, so it's limited to internal, reportedly.

I asked them to do the plugs and wires, because it's got 116k miles on it. I wanted a tuneup. and, yes, $1100 sounded high, but since I'd heard it cost $900 in the past, it didn't give me a total red flag. dealer around here would charge $600 for the water pump, and probably $900 for the opti. and they've done a number on my car before (that was the last time I took it to them).

so, can someone help me out? what should I be looking for here (besides a new car)?

You really got yourself into a pickle. I suggest you get a second opinion on what needs to be done. If they removed the intake and screwed up the install they should be responsible to fix it or refund your money. I think you can have some other shop fix there screw up and make them pay for it. I would just talk to them about what they are going to do to make this right and see if they are stand up guys. $3300 for head gaskets. I have seen complete rebuilds with labor for not much more! I personally would try to get back some of my cost and find a better shop to work on your car. I swore after paying $750 for an egr valve and a power steering pump fix that I would do all my own work and not be a victim again. I feel bad for you, having been there way too many times myself. Good luck!

Can't agree more. I learned on a head replacement done by someone. You have such a HUGE asset base with this board to solve EVERY problem that could come up on your car.

It's too bad you didn't find this site sooner. You'll get some good help here. Hopefully, you're handy with a wrench, have a place to work on your car, and will be able to do some of your own work. Otherwise, it could add up quickly, as you've learned.

can anyone tell me what the fair going rates are for the following, by themselves:
-water pump replacement
-opti replacement
-intake Motorvac cleaning

the second shop quoted me $1800 for head gaskets and then amended it to $2200 for conservatism. is that even fair?

thus why I'm here begging. $3300 is not an option, although I don't know how I can sell it with an unresolved problem...

$700....and no lingering problems for several months would grant a reprieve, possibly. but I need to get it right this (second) time. and I'm going to be talking to the owner of the second shop. I think he'll do a copout, though. my only chance in recuperating some of that cost is if shop#2 finds that shop#1 either didn't do what they said or intentionally screwed something up.

I got a quote from my chevy shop no more than a year ago.

New GM Opti, Waterpump, plugs and wires with labor was going to be $1160.

I thought it was high since the labor was close to the amount in parts.

But again, that was their quote.

Wow, and I thought that I had it bad.
-Ivan

All the years I've been here, and never heard of Motorvac. On finding their website, it appears that the dump some cleaner into the intake and let the engine idle, then follow up with some cleaner in the fuel tank. The cost of that should be about the cost of the materials.... probably less than $10, and very easy to DIY. There are numerous threads here dealing with a specific product that is very popular for that fix. And it wouldn't have damaged the intake manifold gaskets.

http://www.motorvac.com/technical_su...uneCT2100.html

With regard to the coolant problem, it appears they did not follow the correct proceudres for bleeding the air out of the LT1's "reverse flow" cooling system. When you checked the coolant reservoir, you checked the wrong place. The coolant level sensor is in the radiator, not in the reservoir. Yes, lack of coolant in the reservoir may indicate a low level in the radiator, but you need to check it. How come you couldn't get the radiator cap off?

The part about a "vacuum in there" makes limited sense. The radiator runs at 18psi. There is a vlave in the cap that opens up as the coolant temperature drops, and allows the coolant from the reservoir to flow back into the radiator to eliminate the vacuum. Again, is appears the original shop was not aware of the correct procedure for eliminating air from the coolant.

You can buy your own GM Opti for about $250. If you allow the shop 4 hours for install, you would add $300-400 for labor.

Water pump price has gone up, but you should only pay for the part, since they had to R&R the pump to replace the Opti. I can't see it costing more than $300 at dealer prices. But you can buy these parts for way less than dealer prices on the I'net, and a rebuilt water pump shouldn't be all that risky, to save even more.

You made yourself an easy target, and they raped you.

Oh, that was years ago, maybe 2000. i bought the housing pieces without the uniform flow honeycomb from internetracing or someplace like that, took apart and used the hotwire sensors from the old one. I've never gotten a code from it.

A water pump is under $200 and the Opti is around $300 depending on the brand. They both need to be pulled to do the opti and it only took me 1 1/2 days to do it myself because I needed to stop to buy more parts. Head gaskets/intake gaskets and head bolts are around $200 and the labor is about 1-2 days depending upon how good you are. Labor for all three should be $1000 to $1500 for all of them but I am sure you will get quoted much more at a repair shop. These are all do able with the right tools and a little mechanical skill. I learned 90% of my skills from this site alone and could do just about anything on my Camaro. I will stay away from the rear and the transmission since they are a little more complicated than I want to deal with.

What he was trying to say is second shop sucks too since LT1 intakes are dry. NO COOLANT IN INTAKE.


A coolant smell is not normal I'd check the water pump install for leaks. It would suck if the water pump replacement is leaking on your new opti


Head gasket replacement on an LT1 is not rocket science; however, if you believe you have a little coolant leak and your tight on cash; buy some GM coolant supplement tabs or bars leak gold (one and the same) it may fix your problem with the coolant leak and won't clog your heater core or radiator.

I didn't "make" myself a target or anything.

about six years ago, I took my car to the only chevy dealer within 15 miles of here because I got a code. AIR pump, water pump and something else were the repairs. It was around $900-1100, if I remember correctly. when I got my car back, I started it up I started smelling gas, and wondered why it was so dang strong in the air. I turned off my car, got out and noticed gas pooling underneath the car. I popped the hood and saw that the fuel lines and harness right beside it had been sliced through in a perfect cut like it was done with a razor blade. WHY THE HELL WOULD THERE BE A RAZOR SLICE THROUGH MY FUEL LINE FROM AN AIR PUMP R&R?????????
they fixed that for free, but within a day of getting it back the O2 sensor right underneath where the gas was spewing under the hood threw a code and it cost $400-450 to replace it. they wouldn't admit that it was their fault, and I had no way to prove it was. I know it in my heart, but couldn't prove it even if I got a lawyer involved. that was my last time at their shop.

then, the only "reputable" shop anyone would recommend in the area was the one I've had this nightmare experience with. I've taken it there for my car's FOURTH AIR Pump repair, third or fourth water pump (and I think those were about $600 each). A radiator ($1100) and a two-part a/c repair (~2700 total). And this is the place around here with the BEST recommendations! The only thing that they've been right-priced with was a brake job that I didn't have time to do myself (~$170 for just replacing pads on the rear set). Of course, that sounds right to me with $70 pads, and they probably just marked up a $30 set.

It's like all the shops anywhere near me are as crooked as a dog's hind leg.