You can put more paste on the back side, or use some spacers so the air can get in behind it.

 

Had the same issue with my 03 Sonoma 2wd a couple years back. During the summer heat here in California it would act like vapor lock no power very sluggish. Went through everything including ignition components it turned out to be the upper catalytic converter. It would get so hot it would restrict exhaust flow just enough not to set a code P0420 but to make the engine run like crap when it is hot out. And it would only do it during the summer heat.

 

 

Thanks, Rhotpursuit. Perhaps I'm missing something.

Given that the objective of the GM design is to transfer heat from the module to the heatsink plate, with the heatsink fins passively dissipating heat, I'm interested in increasing the passive heat dissipation (i.e., fin area).

Putting space between the module and the heatsink plate seems like a counterintuitive way of increasing heat transfer. Seems like this would reduce heat transfer, and subsequent heat dissipation by the fins. Putting more paste between the module and the heatsink seems like exactly the opposite of spacer(s) between module and heatsink. I don't know the actual physics of the thermal paste; is more paste going to increase heat transfer?

Thanks for your time.

Anyone know of a "high performance" product that enhances the existing design to get rid of more heat?

 

Thanks, Rhotpursuit. Perhaps I'm missing something.

Given that the objective of the GM design is to transfer heat from the module to the heatsink plate, with the heatsink fins passively dissipating heat, I'm interested in increasing the passive heat dissipation (i.e., fin area).

Putting space between the module and the heatsink plate seems like a counterintuitive way of increasing heat transfer. Seems like this would reduce heat transfer, and subsequent heat dissipation by the fins. Putting more paste between the module and the heatsink seems like exactly the opposite of spacer(s) between module and heatsink. I don't know the actual physics of the thermal paste; is more paste going to increase heat transfer?

Thanks for your time.

Anyone know of a "high performance" product that enhances the existing design to get rid of more heat?

The first suggestion is what I did to mine. The second was just a thought. I was thinking that increased airflow over/around the heat sink might cool it better since it's sitting on a steel plate that's attached to the intake.

 

Thanks, Enigma. I can see how that could affect power. I'm not getting codes indicating a converter problem.

I'm having total engine shutdown, and coasting to the curb. It "feels" like the fuel supply is cut off, and I've seen other posts online about S10s and Blazers having vapor lock-like symptoms. Wait a few minutes, and it'll start, but will only run for a few minutes. Let it really cool down on the side of the road, and it drives like normal until it gets hot again.

This can be exciting, even on the two-laners in our part of the world.

I appreciate your time.

 

When's the last time you changed the fuel filter? That also can cause a similar issue. They get all full of dirt then you hit a bump and it stairs it up and plugs up the filter then after it settles it'll run again. Had that issue when I had my Astro van.

 

Excellent question. The fuel filter was changed about 1500 miles before the most recent event. Under load, in ambient temps below 100 degrees or so, it has been fine after the episode I described.

The fuel pump has about 40,000 on it. Fuel system pressure at the Schraeder valve on the fuel rail is normal. And, earlier this summer I flushed the cooling system, changed the radiator, thermostat, water pump, all hoses, and coolant. Plugs, cap/rotor were changed recently. Vehicle has about 160k on it.

Generally, it runs with the temperature gauge centered. It's under load, in the heat, that we've experienced engine shutdown.

I've run through possibilities associated with fuel, and am pretty sure we're dealing with a heat failure in the ignition control module.

Thank you.

 

You can do a fuel pressure test and see if your fuel pump going bad. Here's a video I did back in 2014 to give you an idea what the fuel pressure should be like.

 

Thanks. I'm actually trying to resolve a different problem. Thanks for your time.

If you have any insight into the specific issue of thermal issues associated with the ignition control module, I'd appreciate your experience.

 

Just throwing in my 2 cents on thermal compound. I've seen it dry and get pretty crusty on computer processors and changing out the compound did help in many cases. It's main purpose is to fill all the tiny imperfections between the two surfaces, the compound/paste generally has a high thermal conductivity.

You can try relocating the module to an area with more air flow, but that may require wiring changes.

You can also try using a larger heatsink, drill and tap holes in it to mount the module to and find somewhere to mount that near the stock location. Might look out of place and/or be in the way of other things though.

Most heatsink fins extend out directly from the surface that is contacting the hot component. GM's design probably suits packaging needs and sacrifices some heat dissipation as a result.

A quick ebay search for heatsinks brings up stocks in many sizes, or you can try and recycle one from an old computer laying in a friend's basement...

I had a 93 cutlass that had the same problem, once it got nice and hot it would simply shut off, cooling it down would get it running again. That module didn't have a heatsink and was mounted in a terrible location. A new module fixed the problem for me in that case.