Overheating at 80 MPH?
 

I recently did a N/A to turbo conversion on my '90 GXL. I mounted a front-mount intercooler and and cork sport bumper. My system is running on a Haltech that has not been professionally tuned yet.

Among other problems, I have a weird overheating problem. First of all, the tempature sensor from the Haltech is very sensitive and my tempature reading (on the dash) changes very quickly.

My problem is that at 80mph in fifth (around 3200rpm), my tempature gauge goes up as if its overheating. When I put the car in fourth gear and bring it to the same rpm, it does not overheat. The problem appears to be something that either happens at a certain load that causes the car to run leaner and overheat or, it could be a turbulence problem caused by the FMIC and the fact that I took off the splash guard.

I'm puting the splash guard back on, but if anyone knows what the problem might be, please let me know.

On a side note, I can't get my turboXS BOV to work. I have it Td off the nipple facing the passenger strut tower. I have my boost gauge, fuel pressure regulator, all Td together. If anyone has any ideas, please let me know!

Bump!

No takers on this one?

By the splash guard I am assuming you mean the under cover between the bumper opening and the susepension crossmember.

yep... That's gotta be on for high speed cooling.


Mark

I'd upgarde your radiator. Do you know what heat soak is.

you need that gaurd...

also don't bother looking at your stock gauge... what does your computer screen reading say? :)

if the timming is way off that'll induce overheating as well.

also the gauge on the dash doesn't hook to the haltech sensor... sounds like yours is??? it should be hooked under the oil filter. it won't work off the haltech sensor.

Also time to look at other variables - thermostat healthy? What kind of fan setup are you using?

The dash temp gauge in the '89-91 cars is basically an idiot light. I recommend having at least a real temp gauge with a front mount. Greddy water temp gauges are VERY reasonably priced.

Dale

Thanks guys. I haven't been able to log on for a couple of days.

I have an awesome Fluidine radiator that has saved my ass more than once.

I run an electric fan that has proven to be very reliable for me for over a year. I also thought that the fan does not do any good above thirty MPH.

By heat soak, I believe that you are speaking of intercooler heat soak. As mentioned, I have a front-mount.

I put the splash guard back on. I also installed a shroud on the fan. I have a new thermostat that came with the engine that I will install when I get a chance. When I get a chance to drive to Texas, I will get my car up to 80mph and see what happens. We have been having military exercises which consist of working 14-16 hour days, seven days a week. Because of this, I haven't really gotten a chance to play with it yet.

As far as my BOV goes: I took my 4000rpm rev limiter off (engine break-in period) and to my dismay, I have no more than 2psi of boost! Vacuum leak? THe boost goes up and then drops back down.

you should data log it so you can tell if its running lean "causing heat", or you're sensor is screwy. you have a very capable diagnosis system, use it.

I'm learning. I'll take a look at it.