gmc typhoon help

**rob2000gt** · 08-18-2013, 05:48 PM

I have this gmc Typhoon that was forced to be my daily drive because my 91 GTA was totaled. I was wondering if anyone could help me with some of the issues I am having. This is my first turbo vehicle and I am at a loss on it. thank you.

**35th-ANV-SS** · 08-18-2013, 08:30 PM

List your issues.

**5.0THIS** · 08-18-2013, 11:26 PM

I know exactly what's wrong. I have a crystal ball.

Wait what was the problem?

**konigandy6** · 08-19-2013, 07:55 AM

Yeah what I would do first is get the truck up on jack stands, and make sure your canooter valve isn't stuck in the open position. Problem solved.

**initechpeter** · 08-19-2013, 09:13 AM

Pictures.

**35th-ANV-SS** · 08-19-2013, 02:37 PM

Maybe he meant the GMC got hit by a typhoon.

**2002ssslp** · 08-19-2013, 03:49 PM

Originally Posted by konigandy6

Yeah what I would do first is get the truck up on jack stands, and make sure your canooter valve isn't stuck in the open position. Problem solved.

Texas Speed has a trick aftermarket canooter valve with a slick Teflon coating. They never stick. The only problem is that you have to open up the rumpege slot .001 to get the fit correct.

**rob2000gt** · 08-19-2013, 04:55 PM

Love the responses lol. One issue is in wont idle smoothly at all, it dies all the time when I come to a stop or put it in gear I know the rough idle and dying is related. It acts like its missing badly. if the a/c is on it idles up a little and it stays running all the time but still misses at idle. Driving it runs perfect plenty of power up to 80% throttle, no missing.
second issue. Over 80% it starts to loss power, still runs smooth engine sounds different turbo drops 2 to 3 lbs of boost but then after about 3 to 4 seconds the boost comes back I don't stay in it after that because there is that thing called a speed limit.
I have done a lot of repairs every thing I have done improved drivability
ac delco plugs cr43ts gapped to .025
o2 sensor and repaired a broken wire
tested ignition control module tested good
intercooler pump and wired it to run all the time
set base timing to 0
msd coil (when I installed this I couldn't go over 1/4 throttle it would cut out. I did plugs and it fixed that issue)
fuel pump and sending unit ( return line was leaking)
egr valve
I did a smoke test on the vacuum system and replaced the bad hoses.
the check engine light is not on
before I disconnected the battery to do the fuel pump I had a codes 43 and 42 stored

**rob2000gt** · 08-19-2013, 05:39 PM

I would love to post a pic but I cant fugure out how to get it from my computer to the forum

**Firebirdjones** · 08-20-2013, 04:49 AM

Been a long time since I've had a Typhoon.

I don't remember what codes 43 and 42 are, but that might be a clue.

Edit: Code 42 is the ignition control ground circuit. So you'll have to dig into the distributor and trace the wires, make sure you have good clean connections and no wires are chafed.

Code 43 is the knock sensor. It pulls timing when knock is present.

So it sounds like you have 2 seperate issues going on here.

**rob2000gt** · 08-20-2013, 09:31 AM

I just hooked up a computer and let it idle and watched the knock when its acts like its missing it shows knock and the timing changes. im not sure if the knock retard is making it run poorly or if something is acting up then the computer is compensating for that with knock retard. If I rev it to 1000 rpms knock goes away and runs smooth.

**Firebirdjones** · 08-20-2013, 09:42 AM

Originally Posted by rob2000gt

I just hooked up a computer and let it idle and watched the knock when its acts like its missing it shows knock and the timing changes. im not sure if the knock retard is making it run poorly or if something is acting up then the computer is compensating for that with knock retard. If I rev it to 1000 rpms knock goes away and runs smooth.

If it's running rough and anything is rubbing or clanging (exhaust for example) it will trigger that knock sensor and pull timing. Knock sensors are cheap though and wouldn't hurt to change it. I would guess it either set that code for accessive knock or it's a faulty sensor.
It's obvious from your description the rough running is causing some sort of knock issue triggering the sensor, that rough running could likely be related to the ignition control ground circuit (the other code you found).

After all that is changed/fixed and you still see knock retard then you would have to start another process of elimination. For instance a few gallons of high octane race gas would tell you if it's false knock or real knock.

**rob2000gt** · 08-20-2013, 06:36 PM

I will change the ignition control module and check the ground I have a one from my GTA that I put in 6 months ago ( had to put one in because the original failed and car wouldn't start) They share the same part which is nice. I just cross referenced the knock sensor that also shares the same part. When my GTA got rearended it ran perfect I was actually able to fix it when something acted up.

**RONS98TA** · 08-21-2013, 03:52 AM

I would also check ALL the grounds on the truck. Start at the battery and work your way around the whole engine bay. Remember your dealing with computer controlled stuff and grounds are very important. A little bit of corrosion and the battery terminals to the frame will cause some serious havoc. Make sure you take OFF every ground you find and clean it down to bare metal. Don't just clean the top of it. Then add a touch of paint or grease to it after you reinstall to prevent rust/corrosion from building back up on said ground. I have done this in the past and solved a bunch of problems.

**rob2000gt** · 08-21-2013, 04:11 PM

Originally Posted by RONS98TA

I would also check ALL the grounds on the truck. Start at the battery and work your way around the whole engine bay. Remember your dealing with computer controlled stuff and grounds are very important. A little bit of corrosion and the battery terminals to the frame will cause some serious havoc. Make sure you take OFF every ground you find and clean it down to bare metal. Don't just clean the top of it. Then add a touch of paint or grease to it after you reinstall to prevent rust/corrosion from building back up on said ground. I have done this in the past and solved a bunch of problems.

Good to know I will also do the ground checks thank you I will post results when I have time to do it.

**rob2000gt** · 08-26-2013, 06:32 PM

update: I removed the msd coil and reinstalled the original coil and now is doesn't die on me but still idles poorly. I did 8.5 mm msd wires not much of a change maybe slight performance gain. I cant seem to find the knock sensor its supposed to be on the back of the engine.