NEW Rough Idle Issue
Thread Starter
Racer
Joined: Jan 2013
Posts: 276
Likes: 5
From: Sarasota Florida
NEW Rough Idle Issue
I'm not sure where to begin! 1987 Corvette.
Long story short I recently did a 9th injector delete and now everything is back together.
I have a misfire on the 1st bank that gets worse at 215 degrees. At that temp it feels like it's sputtering and surging trying to find a steady idle.
Below 215 degrees I can somewhat feel it but it's not terrible unless I floor it. It'll accelerate like normal until about 50MPH and 3200 RPM. The engine will rev up but won't kick into upshift so the car revs high but isn't accelerating. It does that for about a second and then engages. I NEVER had an issue like this before I did that delete. Now I'm not blaming the 9th injector missing to cause all this, it's just odd. I do have used ACDelco 7mm wires which could be the cause, but why now? Plugs are not fouled. I'm totally stumped as to why I'm having this issue. Electronic spark control module? Knock Sensor? Faulty TPS? I will be pulling codes hopefully sometime today.
Long story short I recently did a 9th injector delete and now everything is back together.
I have a misfire on the 1st bank that gets worse at 215 degrees. At that temp it feels like it's sputtering and surging trying to find a steady idle.
Below 215 degrees I can somewhat feel it but it's not terrible unless I floor it. It'll accelerate like normal until about 50MPH and 3200 RPM. The engine will rev up but won't kick into upshift so the car revs high but isn't accelerating. It does that for about a second and then engages. I NEVER had an issue like this before I did that delete. Now I'm not blaming the 9th injector missing to cause all this, it's just odd. I do have used ACDelco 7mm wires which could be the cause, but why now? Plugs are not fouled. I'm totally stumped as to why I'm having this issue. Electronic spark control module? Knock Sensor? Faulty TPS? I will be pulling codes hopefully sometime today.
Last edited by Stephenms; Sep 29, 2014 at 09:02 AM.
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
1st bank? Of what? The injectors? How did you determine this?
Thread Starter
Racer
Joined: Jan 2013
Posts: 276
Likes: 5
From: Sarasota Florida
Could it possibly be that I switched the EGR solenoid vacuum lines? I rearranged the two lines that run from the canister to the solenoid, then to the EGR. The idle got better in reverse and drive and throttle response at idle is much better. Have yet to do a road test but I will tonight on my way home. I know I have done that before and it did have a terrible idle like it was but it never had a misfire, I knew it felt familiar the way the car was vibrating and searching for idle rapidly. Certainly could have been a fix, will keep you guys updated!
Last edited by Stephenms; Sep 30, 2014 at 03:01 PM.
Thread Starter
Racer
Joined: Jan 2013
Posts: 276
Likes: 5
From: Sarasota Florida
I've been looking into a delete but am coming up empty on google. I would rather not put my car into ANOTHER DIY project due to it being my daily driver, so hopefully that EGR solenoid vacuum line was the culprit of my misfire
Thread Starter
Racer
Joined: Jan 2013
Posts: 276
Likes: 5
From: Sarasota Florida
The vacuum lines to the EGR solenoid DID NOT fix my misfire. It ran okay at start up but once it got up to temp, 170+ it started to have rough idle again and misfiring, lack of acceleration, slipping when trying to Upshift after I punch it. I had it tuned to 6 degrees which it liked before. I will be replacing the wires with a Delphi set. I can feel the misfire at normal driving speeds,45 and up. I'm really stumped as to why this is happening all of the sudden. Could it be that I need to reset codes?
Maybe the EGR switch itself?
Maybe the EGR switch itself?
Last edited by Stephenms; Sep 30, 2014 at 10:48 PM.
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Drifting
Joined: Aug 2010
Posts: 1,704
Likes: 8
I'll start from codes reading,any SES light comin'on? read codes and report down,this condition can't be ignored by sensors/ ECM,you must have codes stored,write down ,reset ECm unplugin' negative at battery,run the car again in various condition and read again codes to confirm new,old or no codes.
Alberto
Alberto
Last edited by tunedport85inject; Oct 1, 2014 at 07:03 AM.
Thread Starter
Racer
Joined: Jan 2013
Posts: 276
Likes: 5
From: Sarasota Florida
I thought it would be spark plug wires too but they check out just fine, everyone is in the proper place. And YES! They do run surprisingly well on lacking cylinders.
It still had a miss at start up. It seems to be random the more I notice it. I think something is making me run extremely lean, it's getting hotter than normal.
The SES usually goes on and off but that's for TPS low volt and MAF burn off relay. Never had a problem with those two. Now the light is always on so I'm gonna read the codes with a code scanner and live feed. I'm hoping this is just something simple and stupid
It still had a miss at start up. It seems to be random the more I notice it. I think something is making me run extremely lean, it's getting hotter than normal.
The SES usually goes on and off but that's for TPS low volt and MAF burn off relay. Never had a problem with those two. Now the light is always on so I'm gonna read the codes with a code scanner and live feed. I'm hoping this is just something simple and stupid
Drifting
Joined: Aug 2010
Posts: 1,704
Likes: 8
If the burn off relay is faulty,you don't have any wire cleaning cicle ,a dirty MAF wire doesn't read the air flow accurately.Do you still have the cat? may be your cat is clogged or startin' to...
Last edited by tunedport85inject; Oct 1, 2014 at 08:13 AM.
Thread Starter
Racer
Joined: Jan 2013
Posts: 276
Likes: 5
From: Sarasota Florida
The MAF was cleaned with MAF specific cleaner and a q-tip.
Last edited by Stephenms; Oct 1, 2014 at 08:22 AM.
Team Owner
Joined: Jul 2004
Posts: 28,353
Likes: 3,253
From: Hartford WI
MAF needs to burn off each time. Not sure when you did it last.
Thread Starter
Racer
Joined: Jan 2013
Posts: 276
Likes: 5
From: Sarasota Florida
Got the codes!
33 MAF malfunction (I think this was stored because I did run the car without it but plugged it back in)
22 Open Throttle Position Sensor Circuit
43 Electronic Spark Timing Malfunction (knock sensor) I checked the wire that goes to the knock sensor and it about half an inch of open wire, could this be grounding off of something causing it to run like poo?
I also reconnected my EGR solenoid pigtail connector, it felt a little loose, now my idle is at 1000.
33 MAF malfunction (I think this was stored because I did run the car without it but plugged it back in)
22 Open Throttle Position Sensor Circuit
43 Electronic Spark Timing Malfunction (knock sensor) I checked the wire that goes to the knock sensor and it about half an inch of open wire, could this be grounding off of something causing it to run like poo?
I also reconnected my EGR solenoid pigtail connector, it felt a little loose, now my idle is at 1000.
Last edited by Stephenms; Oct 1, 2014 at 01:24 PM.
Drifting
Joined: Aug 2010
Posts: 1,704
Likes: 8
code 43 is related to Electronic Spark Control
code 22 TPS signal voltage low (do you mess with minimum idle? set TPS to .54V per factory procedure)
code 33 means MAF sensor high,i hope this is not result of Maf cleaning
to ceck the knock sensor ,warm up the engine,put it at 1500 rpm,tap with a screw driver near the sensor and ceck for rpm drop meaning the knock is sending the signal and ESC shut off with a lower than 6 volt voltage at terminal b7.This code is only set in case the knock isn't functioning.Normally the ECMs simulates once per start a knock condition only to ceck the system.
reset codes and ceck again to confirm codes,then we can go deeper for each code.
code 22 TPS signal voltage low (do you mess with minimum idle? set TPS to .54V per factory procedure)
code 33 means MAF sensor high,i hope this is not result of Maf cleaning
to ceck the knock sensor ,warm up the engine,put it at 1500 rpm,tap with a screw driver near the sensor and ceck for rpm drop meaning the knock is sending the signal and ESC shut off with a lower than 6 volt voltage at terminal b7.This code is only set in case the knock isn't functioning.Normally the ECMs simulates once per start a knock condition only to ceck the system.
reset codes and ceck again to confirm codes,then we can go deeper for each code.
Last edited by tunedport85inject; Oct 1, 2014 at 02:11 PM.