PontiacBonnevilleClub.com

The Grizz melted the plastic loom covering the wires to the EGR valve.
The melted black plastic dripped down onto the exhaust crossover pipe and started to smoke.



That's too hot!!!

What kind of engine temps did he see?

engine temps or exhaust temps?

since it was the EGR, I'm guessing exhaust temps....which would signal that its running extremely lean. if so...you might want to check the fuel pressure.

Yes engine temp and exhaust temp.
The fuel filter is new.
The engine runs around 210 F
The plastic melts at 250 F
The exhaust manifolds are 650 F

I would do a 180 T-stat and the fan relay override asap. I did this in my 93 and it always stays at 180 no matter what.

I think the key is the fans.
It already has a drilled 180 stat but the fans don't come on until the temp is 210 F

Maybe the fan over ride will be a WCBF mod......

Yes you are correct. I had the exact same problem and the fan override is what fixed it. I have mine wired directly instead of with a switch which I may do sometime down the road, but for now it always runs at 180 in the summer and winter. I just used a splice that you wrap around the two wires and just squeeze closed and your done. I ran it to the strut bar bolt with a ring terminal. I did this all about a year and a half ago.

I couldn't wait a week so did the high speed fan over ride switch.
Wow that was much simpler than on my car.
The Grizz now has two mods. 180 drilled stat and now this.

Thanks for the explicit instructions Bill.

Paul, I didn't know the background. I gaurantee I was hotter today, and you should NEVER see those temps up there.

There is something else wrong with that car. I suspect two things. Inefficient cooling (perhaps a corroded radiator core?) and running lean.

I've run my cars in EXTREME temps (120 ambient, amplified by road heat) and have never melted loom even on my EGR valve.

How can we correct the lean condition?
AFPR?
New fuel pump?

I know it's always 10 F warmer where you are. Only 80 F here now.

No AFPR. It shouldn't run lean for a good many mods.

You have either a pressure or flow issue with the fuel IF you're running lean, OR you have a vacuum leak. You need to scan for LTFT and STFT.

I suspect it is a dirty rad
The outside of it is fouled with oil that had leaked from a loose trani cooler fitting. I cleaned up as much as I could off the A/C condenser fins but don't know how bad it is inside.

I will check fuel trims if the scanner that John lent us will do that. Will it read similar units to mine like negative, zero and positive percentages?
So if it's running lean, the LTFT should show positive numbers.

I know my 00 is running rich because the LTFT is -10 and the wideband O2 reads 10:1 at WOT.

OK, we just came back from a scan run and the LTFT is 130 on heavy acceleration and 160 normally. What does that mean?

The coolant temp stayed at 180 F

No KR.

With a fresh engine and near perfect compression, this Green Grizz moves pretty good.

Right front tire is leaking down to 15 psi over 24 hrs.

Paul,I have had the same heat issues with my 93,today I put a 180 drilled thermostat along with a new temp sending sensor.My car now runs 195 even in the city,I sat at the bowling alley waiting for my daughter for 20 minutes and it never got over 200 degrees.Just a thought,not sure if you changed the sending unit on that car,yours may have different issues,but it sure sounded alot like mine. Tim

Paul, 128 is essentially the zero point for fuel trims. How about finding out how the car was driven before the overheat?

You may want to put something in there to flush out the cooling system, run it for awhile, then change it out.

With your weather up there, you shouldn't need to rely on the high speed fan override to keep under 200 F.

I'd like to see you repeat the test but get LTFT, STFT & MAF frequency. Can you get all three readings at idle, WOT & cruising at 45 mph.

I was in the car and watched the gauge climb to almost the red and I also shot the engine with the temp gun.

It runs at 180 now with the fans turned on.

Bill, we don't have a reprogrammed PCM with the fan turn on changed to 180 so it will run at the factory design of what seems to be 200 F - 220 F

I checked both temp sending units using a hot water resistance test and they are both within specs.

2000Silverbullet wrote:I suspect it is a dirty rad
The outside of it is fouled with oil that had leaked from a loose trani cooler fitting. I cleaned up as much as I could off the A/C condenser fins but don't know how bad it is inside.

you have mentioned that radiator from day one, iirc, before the engine was out of the car. Can you find a decent used one, if new is too expensive?