# 34 on a 1987
Thread Starter
Acct disabled by request 16 Aug 2009
Joined: Sep 2002
Posts: 498
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# 34 on a 1987
I've been trying to get rid of a code 34. Put in a new prom - it idles better, but still the code. Cleaned off the MAF sensor - no change, still the code. I don't see anything wrong with the MAF sensor - all seems intact. Could it be the MAF Power and Burnoff Relay...? Or does anyone have other suggestions.
Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
The light will blink three times in a row...pause...blink four times in a row. You should have gotten a code 12 before and after the code 34. Here is what to do : check for loose or damaged air duct. Disconnect the battery and clear the codes. Reconnect and (do not ground the ALDL), and start the engine and run above 2000 rpm for 1 minute or until the light comes back on. Now turn the engine off and turn the key to on and ground the terminal.
If the code is still there, disconnect the battery again and clear the code. ALDL not grounded, disconnect the MAF sensor and start the engine and run above 2000 rpm for one minute or until the light comes back on. Now turn the engine off and turn the key to on and ground the terminal.
If the code 34 is still there check for short to ground in the dark green wire at the MAF. Have the connector off and use a voltmeter and test the dark green wire with the key on. It should show 5v when tested and if it doesn't, check the dark green wire at the ECM. The ECM could be faulty if there is not 5v there.
If a code 33 shows up after doing this. The MAF is bad and needs to be replaced.
This comes directly from my 86 FSM. Maybe this will get you in the right direction. My guess is that it is a loose connection or a shorted wire.
If the code is still there, disconnect the battery again and clear the code. ALDL not grounded, disconnect the MAF sensor and start the engine and run above 2000 rpm for one minute or until the light comes back on. Now turn the engine off and turn the key to on and ground the terminal.
If the code 34 is still there check for short to ground in the dark green wire at the MAF. Have the connector off and use a voltmeter and test the dark green wire with the key on. It should show 5v when tested and if it doesn't, check the dark green wire at the ECM. The ECM could be faulty if there is not 5v there.
If a code 33 shows up after doing this. The MAF is bad and needs to be replaced.
This comes directly from my 86 FSM. Maybe this will get you in the right direction. My guess is that it is a loose connection or a shorted wire.
Thread Starter
Acct disabled by request 16 Aug 2009
Joined: Sep 2002
Posts: 498
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Code 34
Thanks. I've done everything up to the point where you mentioned volt meter. I'll have to get one and try that. When I unhooked the wires plugged in to the MAF it barely ran, but I didn't look at the wires. Thanks again.
Le Mans Master
Joined: May 2005
Posts: 5,214
Likes: 65
From: Queensland, AUSTRALIA
36 is for the burnoff relay, but when this was happening on my 87 i was getting code 34 as well (and no 36). There should be 2 relays that are the same, one is the MAF burnoff relay, swap them over and see if the problem is still the same or if it changes. I dont think the relays are expensive, and since the car is still running normal or close to it, id be looking towards the relay.
Thread Starter
Acct disabled by request 16 Aug 2009
Joined: Sep 2002
Posts: 498
Likes: 0
Code 34
Thanks for your response. I ordered new relays the other day, so will test out what you said soon. Thanks.
I passed emissions testing again today with flying colors. Hope to get rid of this code soon.
I passed emissions testing again today with flying colors. Hope to get rid of this code soon.
Instructor
Joined: Jul 2006
Posts: 138
Likes: 0
From: Eagle River Alaska
34 staying lit
Hey thanks for having the same problem as my 86! I'm going to get a new relay tommorow and see if it works for me! I am having the same problem with no luck, I followed my FSM and replaced the MAF twice just to make sure I didn't get a faulty one, check for vacuum leaks (none), checked for shorts etc., removed hypertech chip and got a new stock prom, tested ecm, and still got the code 34. Hopefully it will shut off when I get a new relay. I'll let ya know! Thanks!
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