Trouble Codes, and Running Poorly
Thread Starter
Melting Slicks
Joined: Jan 2010
Posts: 2,024
Likes: 4
From: Austin TX
Trouble Codes, and Running Poorly
Hey, I've got an 88, Auto, stock
I seem to have a few issues, mainly with the way the car runs.
It seems to be showing codes:
Code #21: Throttle Position Sensor Circuit High.
Code #32: EGR System Failure.
Code #34: Mass Air Flow Sensor Low.
On to the behavior. It starts and drives fine. Idle sits at around 600-800 in neutral. In terms of driving, it accelerates at a normal pace at light throttle, but at WOT, it's like I'm driving a moped. There's seriously no power.
I thought it might be a timing issue, so I got my timing light and checked my timing. The timing line is jumpy. It's not stable and jumps around a bit.
Spark plugs are fine, wires are fine, distributor cap and rotor are new. I'm really not sure what to check into. I don't want to blindly replace parts.
Any advice?
I seem to have a few issues, mainly with the way the car runs.
It seems to be showing codes:
Code #21: Throttle Position Sensor Circuit High.
Code #32: EGR System Failure.
Code #34: Mass Air Flow Sensor Low.
On to the behavior. It starts and drives fine. Idle sits at around 600-800 in neutral. In terms of driving, it accelerates at a normal pace at light throttle, but at WOT, it's like I'm driving a moped. There's seriously no power.
I thought it might be a timing issue, so I got my timing light and checked my timing. The timing line is jumpy. It's not stable and jumps around a bit.
Spark plugs are fine, wires are fine, distributor cap and rotor are new. I'm really not sure what to check into. I don't want to blindly replace parts.
Any advice?
Melting Slicks
Joined: May 2010
Posts: 2,082
Likes: 3
From: Conowingo Maryland
I think the answers are in your codes esp the esp code 34 and 21. I would work on the codes and go from there. I do not have a way of scaning the diag tree for the code repairs so if you do not speak up and someone on here may be able to do that for you. I would not go any futher till I got this information
Melting Slicks
Joined: May 2010
Posts: 2,082
Likes: 3
From: Conowingo Maryland
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
You can eliminate the MAF by unplugging it. The engine will run just fine with it unplugged.
I suggest resetting the error codes to make sure you're really looking at a problem. Unplug this connector for a second or so:
I suggest resetting the error codes to make sure you're really looking at a problem. Unplug this connector for a second or so:
Instructor
Joined: May 2013
Posts: 177
Likes: 0
From: Fairland Oklahoma
I thought it might be a timing issue, so I got my timing light and checked my timing. The timing line is jumpy. It's not stable and jumps around a bit.
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Instructor
Joined: May 2013
Posts: 177
Likes: 0
From: Fairland Oklahoma
I've done that a couple times haha always messes with my mind at first 
Edit: I forgot to mention that the problem you mentioned with wot sounds like the tps. I had the exact same problem. Completely bogged at wot. Set my tps and it was fine after that.
Edit: I forgot to mention that the problem you mentioned with wot sounds like the tps. I had the exact same problem. Completely bogged at wot. Set my tps and it was fine after that.
Last edited by Christian95; Jun 27, 2014 at 10:02 PM.
Thread Starter
Melting Slicks
Joined: Jan 2010
Posts: 2,024
Likes: 4
From: Austin TX
And one of the vacuum lines to my EGR is cracked. So, that seems to solve all my problems! Is there a place to buy the EGR vacuum lines or am I pretty much on my own for a DIY solution?