Solved odd problem with my car - bogging, rough idle
Thread Starter
Joined: Jan 2002
Posts: 15,622
Likes: 2,724
From: Pensacola, FL
Solved odd problem with my car - bogging, rough idle
This was a weird one that popped up after I worked on my car this weekend. I changed the O-ring that is between the two halves of the Y-pipe to solve a minor boost leak, which requires taking a TON of stuff off the car - turbo inlets, air pump, crossover pipe, etc.
After doing the job, the car idled a bit lower than normal, had a little less vacuum on my boost gauge, and gave a stutter and hesistation on and off throttle. The 3000 RPM hesitation was actually worse as well.
Had an inspiration pulling into the parking lot here at work after lunch. When I was working on the car, the air pump electrical connector (which is pretty broken and has some insulation missing off one wire) touched the water pump housing and I got a spark. I didn't think much of it, as I wrapped up the exposed wiring and re-covered the wire. I figured the car wouldn't run, as it would probably blow the fuse for the EFI system.
Well, as I got in the parking lot I popped the hood, and lo and behold the air pump wasn't running! The connector was connected and secure. I shut the car off and checked fuses - on a hunch, I looked at the AC fuse in the big fuse block under the hood by the strut tower. Sure enough it was blown! Dug a spare 15amp fuse out, and I was back in business.
Car now runs fine, idles fine...just like it used to. Woohoo!
I believe the two magnetic clutches (on the AC compressor and on the air pump) both get power from the same hot 12v power source (through the AC fuse) and are switched on by the other wire grounding out. I'm going to read up on this circuit tonight in my shop manual.
I believe the ECU accounts for extra air from the air pump when it looks at the oxygen sensor, since some of the air is injected in the exhaust manifold. Without the air pump running, the fuel maps are off a bit, and you get the before-mentioned problems.
Anyhow, thought I'd share - hope this helps someone else out! I was pretty puzzled as to the problem!
Dale
After doing the job, the car idled a bit lower than normal, had a little less vacuum on my boost gauge, and gave a stutter and hesistation on and off throttle. The 3000 RPM hesitation was actually worse as well.
Had an inspiration pulling into the parking lot here at work after lunch. When I was working on the car, the air pump electrical connector (which is pretty broken and has some insulation missing off one wire) touched the water pump housing and I got a spark. I didn't think much of it, as I wrapped up the exposed wiring and re-covered the wire. I figured the car wouldn't run, as it would probably blow the fuse for the EFI system.
Well, as I got in the parking lot I popped the hood, and lo and behold the air pump wasn't running! The connector was connected and secure. I shut the car off and checked fuses - on a hunch, I looked at the AC fuse in the big fuse block under the hood by the strut tower. Sure enough it was blown! Dug a spare 15amp fuse out, and I was back in business.
Car now runs fine, idles fine...just like it used to. Woohoo!
I believe the two magnetic clutches (on the AC compressor and on the air pump) both get power from the same hot 12v power source (through the AC fuse) and are switched on by the other wire grounding out. I'm going to read up on this circuit tonight in my shop manual.
I believe the ECU accounts for extra air from the air pump when it looks at the oxygen sensor, since some of the air is injected in the exhaust manifold. Without the air pump running, the fuel maps are off a bit, and you get the before-mentioned problems.
Anyhow, thought I'd share - hope this helps someone else out! I was pretty puzzled as to the problem!
Dale
What's your point ?
Joined: Feb 2001
Posts: 3,573
Likes: 0
From: Gainesville, Fla.
You'll find the ECU shut's both the air pump, and A/C clutches off abouve 3k on hard accelleration. Not sure if this is whee your going with it, but thought it would give you a place to look. Jack
Originally Posted by DaleClark
This was a weird one that popped up after I worked on my car this weekend. I changed the O-ring that is between the two halves of the Y-pipe to solve a minor boost leak, which requires taking a TON of stuff off the car - turbo inlets, air pump, crossover pipe, etc.
After doing the job, the car idled a bit lower than normal, had a little less vacuum on my boost gauge, and gave a stutter and hesistation on and off throttle. The 3000 RPM hesitation was actually worse as well.
Had an inspiration pulling into the parking lot here at work after lunch. When I was working on the car, the air pump electrical connector (which is pretty broken and has some insulation missing off one wire) touched the water pump housing and I got a spark. I didn't think much of it, as I wrapped up the exposed wiring and re-covered the wire. I figured the car wouldn't run, as it would probably blow the fuse for the EFI system.
Well, as I got in the parking lot I popped the hood, and lo and behold the air pump wasn't running! The connector was connected and secure. I shut the car off and checked fuses - on a hunch, I looked at the AC fuse in the big fuse block under the hood by the strut tower. Sure enough it was blown! Dug a spare 15amp fuse out, and I was back in business.
Car now runs fine, idles fine...just like it used to. Woohoo!
I believe the two magnetic clutches (on the AC compressor and on the air pump) both get power from the same hot 12v power source (through the AC fuse) and are switched on by the other wire grounding out. I'm going to read up on this circuit tonight in my shop manual.
I believe the ECU accounts for extra air from the air pump when it looks at the oxygen sensor, since some of the air is injected in the exhaust manifold. Without the air pump running, the fuel maps are off a bit, and you get the before-mentioned problems.
Anyhow, thought I'd share - hope this helps someone else out! I was pretty puzzled as to the problem!
Dale
After doing the job, the car idled a bit lower than normal, had a little less vacuum on my boost gauge, and gave a stutter and hesistation on and off throttle. The 3000 RPM hesitation was actually worse as well.
Had an inspiration pulling into the parking lot here at work after lunch. When I was working on the car, the air pump electrical connector (which is pretty broken and has some insulation missing off one wire) touched the water pump housing and I got a spark. I didn't think much of it, as I wrapped up the exposed wiring and re-covered the wire. I figured the car wouldn't run, as it would probably blow the fuse for the EFI system.
Well, as I got in the parking lot I popped the hood, and lo and behold the air pump wasn't running! The connector was connected and secure. I shut the car off and checked fuses - on a hunch, I looked at the AC fuse in the big fuse block under the hood by the strut tower. Sure enough it was blown! Dug a spare 15amp fuse out, and I was back in business.
Car now runs fine, idles fine...just like it used to. Woohoo!
I believe the two magnetic clutches (on the AC compressor and on the air pump) both get power from the same hot 12v power source (through the AC fuse) and are switched on by the other wire grounding out. I'm going to read up on this circuit tonight in my shop manual.
I believe the ECU accounts for extra air from the air pump when it looks at the oxygen sensor, since some of the air is injected in the exhaust manifold. Without the air pump running, the fuel maps are off a bit, and you get the before-mentioned problems.
Anyhow, thought I'd share - hope this helps someone else out! I was pretty puzzled as to the problem!
Dale
but congrats on the find
Thread
Thread Starter
Forum
Replies
Last Post
blkops
3rd Generation Specific (1993-2002)
7
Aug 12, 2015 01:30 PM
