I'm new to these boards and just got my car back in July, so I'm still learning about it.

Last night driving home the SES light came on while on the freeway.

All of the gauges looked normal, though the voltage gauge was sticking right below 13V (around 12V), and didn't fluctuate with different engine speeds. I thought maybe I was running off of the battery at that point and that my alternator went out.

I searched around on these boards and found how to read the error codes.

I'm getting a code 32. Best I can tell, this is an EGR circuit fault or MAP sensor circuit open.

I'm new to these cars; can anybody tell me what to do/check? Could I still possibly have a bad alternator (or something else)? I'm used to the gauges moving around while driving, so just having it sit there concerns me even though it doesn't seem to have anything to do with the SES code.

What do I need to do with the SES code 32?

I have a '87 IROC with the 305 TPI engine and auto tranny. Both have been rebuilt within the last 20k miles; the engine was bored out to 350cid during the rebuild, but I'm pretty sure everything else is normal 305 accessories.

Alternator is about 8 years old, starter and battery are new this year, the EGR system was replaced about 8 years ago as well.

Any help is appreciated. The car has been great and this is the first problem I've had since I got it.

Thanks!
mr.bri

 

Check the EGR, its on the manifold. Just make sure the vacuum tubes are plugged in properly and that the diaphraghm moves up and down nicely.

The EGR valve is a big brass colored object bolted ontop of your intake manifold underneath the TPI intake.

In 8 years it could be clogged up with carbon deposit and siezed up.

 

Thanks! I'll check it out once I get home today. Hopefully it's not too hard to get apart!

As far as I know they cleaned everything up when they did the engine rebuild. Is it common for the EGR to get clogged up in ~20k miles/3 years?

Does it often just throw a code while driving down the road (at a steady speed)?

Will a bad alternator (or related part) throw a code? I didn't see it listed on the code list.

Sorry for all of the questions..... I really like the car and I need it to last me for a while being as reliable as possible! It has 223k on it and I was hoping to get a few more out of it without too many problems.

Thanks again!
mr.bri

 

Mr. Bri,

Welcome Aboard!

Just a few points, not necessarily in any order:

The alternator will not directly cuase an error code - i.e., there is no trouble code for "Failed Alternator". There are, however, codes that indicate a system overvoltage or undervoltage.
16 - System over voltage - over 17.1 volts,
53 - System over voltage - over 17.1 volts,
54 - Fuel pump voltage low (below 2 volts) (EFI/TPI/SFI.

The EGR error code will generally only appear when the car is driven at road speed, at a moderate throttle opening, under light load (cruising). The only exception on your car is if the diagnostic temperature switch or EGR vacuum solenoifd is shorted or disconnected.

The EGR valve (and temperature switch) are not that easy to access on a TPI engine. They are buried under the intake plenum:





Many times the EGR fails as a result of carbon buildup in the exhaust passages, as Slade suggested.

If you remove and clean the valve, DO NOT use any solvents on the valve pintle. Do whatever you like with the exhaust passages, but solvents can damage the internal pilot valve in the EGR, rendering it useless. Chances are you have a negative backpressure type EGR valve, so you need to observe that precaustion.

Good luck with your project.

 

Thanks guys! This board is REALLY helpful!

Looking at the TPI setup, I think this may be something for a weekend rather than a few minutes after work before it gets dark.

Sounds like (HOPEFULLY!) it's just the EGR, and drivability w/ the code was fine.

Thanks again!

mr.bri

 

As insurance against the possibility that you have a failed EGR valve, it might be a good idea to line up a parts supplier that has a replacement on hand before you start your project - just in case.

It probably is a good weekend project, since you'll also need to have a set of plenum gaskets, a TB gasket, torque wrench, T-20 Torx driver, 10mm deep socket, and a T-40 Torx bit before you begin (along with other more common hand tools). If you remove the throttle body as shown in the photo, you won't need to drain the cooling system. When you reassemble, make sure you route the throttle cables as they were before you begin, since one is routed through the ineer side of the runner tubes, and is very difficult to install from the outside after the plenum has been replaced.