EGR O2 Question

ChunkFunky · 07-07-2003, 04:36 PM

ok, I had stock headers for a while and each side had a broken stud, so each side of teh H pipe had an exhaust leak. I finaly got new BBK headers in place and bolted it all up nice and I'm getting a check engine light after about 10-15 minutes of driving... I pulled codes and got 31, 41, 91... 31 is something with the EGR and the 41 and 91 are O2 leans... though not sure why there's TWO codes, unles it's one per side... this is the only mod I made...the only thing I can add is, one of the vacum lines on teh pass fender area that comes from that 4 way vacum distro and goes to the first valve on teh AIRPUMP tubing got melted. so I cant tell if it's sealed off and cauterised ...or leaking... eitherway... that's not an ENGINE vacum source anyway, is it?.. woudl that cause enough of a vaum leak? the tube is that hard plastic stuff.. i'll try to get a new one... but it just seems so miniscule to make these codes come up. though I cant imagine what else it could be, unless the EGR went bad coincidentaly... or the O2s are crapped up from having so much of an exhaust leak before them..
-as

PKRWUD · 07-08-2003, 08:01 AM

41 and 91 are your two O2 sensors. 31 means the EGR valve position sensor, that measures how much the EGR valve is opening, isn't working.

You need to make sure that all the vacuum lines are functional, and attached. If that doesn't clear the code, then unplug the the harness at the sensor, and run a jumper wire between the orange/white wire and the brown/green wire, in the harness connector. Run KOEO self test again, and look for a code 35. Ignore all other codes. If code 35 comes up, remove the jumper and replace the sensor.

The exhaust leak you had allowed extra air to enter the exhaust, and may have damaged the O2 sensors, but more than likely caused the ECM to learn a false setting. I would first try resetting the ECM, and then doing a relearn on it, and see if the O2 codes come back. If they do, you may have to replace them.

Take care,
~Chris

ChunkFunky · 07-08-2003, 08:40 AM

I did disconnect the battery for a while.. probabaly about 30 minutes.. that should be enought to reset it right?

I'll try the code 35 test thing.. what would 35 signify?

does this mean I'm running lean or just that the O2s seem to think so... I'm driving to CA on saturday and if I cant get this resolved by then will it be a problem? The cars drives fine.. but I dunno if I can get an EGR by then IF that's the problem.. I'll check the junk yards

-as

PKRWUD · 07-08-2003, 01:30 PM

Yeah, 41 and 91 mean that the system is lean. 42 and 92 mean that the system is rich.

Code 31 means that the EVP sensor signal voltage is below the minimum. Disconnecting it and jumping those two wires will send the VREF back to the ECM as the sensor signal voltage, which would be too high, and it will trip a code 35. If that happens, then you know the system is working, and the fault has to be in the sensor.

Yes, 30 minutes should be long enough, but to be safe, do it again, but this time turn on the headlight switch after the battery is disconnected. This will ensure that the capacitors are completely drained, resetting the ECM.

Driving it with the ECM thinking the system is lean will cause it to run rich. Running rich, across the country, will kill your wallet in the cost of gas, plus you run the high risk of clogging any cats that you might have.

Take care,
~Chris

ChunkFunky · 07-08-2003, 01:50 PM

Man... you are an quite an asset to the world... when I get out to California I'm going to buy you a beer or something.. or a keg.. or maybe a bottling plant... if I have any money left over from paying for gas...

these codes were all in CONTINUOUS memory... and I got 11 for the KOEO test... I'll disconnect it again today and see what I come up with...it's a new code since the light comes on just about about 10 minutes.. wich is about warm up time I suppose... makes sense I guess.... I dont have to worry about my cats since I dont have any.. though I'll be getting a set when I get to CA...

thanx for your help... for someone who doesnt even own a ford you sure have all the answers...

I read somewhere you were an olds guy... I was an olds guy till I found out I was moving.. so I had to sell my 72 cutlass... it need alot of work, damn new england winters eat cars for breakfast... I hope to find a nice W-30 convertible when I get out there.. anyway...
-as

PKRWUD · 07-08-2003, 02:08 PM

LOL! For the record, I have owned several Fords, including the F150 I drive now. It's a Mustang that I've never owned.

I love Olds engines, and I love the older cars. I've got a 400ci out of a 1966 4-4-2 in my garage, waiting patiently for me to win the lottery so I can rebuild it.

There are TONS of classics out here. They simply don't rust, and seem to last forever. If you want it, you'll be able to find it once you get here. Where abouts are you headed to?

ChunkFunky · 07-08-2003, 08:29 PM

first the business.. then the BS...

I it's 9:30 PM, I disconnected my battery... I will reconnect it before work tomarrow morning.. I turned on the HIGHLIGHT switch too.. that should do it... I'll drive to work and if the light comes on.. I will check my codes... if I get the 31, 41, 91 then I will do the jumper thing... if I get the 35, that means the sensor is bad...and I will go to the junk yard and get sensor... I actulay was there today and pulled that vacum harness from a grandmarquis.. it had the ford 5.0 I was going to snag that EGR but it looked different.. it didnt have a vacum line going to it for one... I'll have to find one that looks like mine I would imagine... or is it just the sensor part that needs to be replaced and not the WHOLE EGR unit... if that's the case will this other one work?

ok... and here's the rest of my boring story...

I'm moving to IRVINE, cause that's where my girlfriend is going to school.... though I bet we'll end up living in costa mesa or tustin or something like that due to cheaper rents and such.. I wont have a job when I get out there .. so I hope I can find one doing what I normaly do.. network administrator stuff... though I suppose worst case I could fix cars or something.... I've never been a big fan of these computer controlled cars.... but my heart is in the old muscle... and oldsmobiles particularly... my plan was to take this 72 cutlass and drop in a 455 but since I'm moving, I sold it... I hope I can find one out there and do it up nice... I like the 71-72 body style.... or the 67 wich is a different look... I didnt like the front ends of the 68-70s as much... but I suppose this is all for another forum. Ventura isnt FAR I see though not aroudn the corner either... are there alot of dragways out there? I have yet to bring the mustang to the track...
-as

PKRWUD · 07-09-2003, 02:12 AM

Some EGR valves have the EVP sensor mounted to them, and some are separate. get the same kind that you have.

Carlsbad is a cute little drag strip that's not very far from Irvine/Costa Mesa. Pomona is close, too. Other than that, there's Palmdale, in the high desert, but that's pretty far. That's where FFW is going to be in the fall.

Ventura is a good 2+ hour drive from Irvine, depending on traffic. Maybe you and your girlfriend can come up to one of our Sprint car races, and hang out in the pits.

Take care,
~Chris

ChunkFunky · 07-09-2003, 06:09 AM

as strange as it may be, my girlfriend enjoys this car stuff.. where most girls wouldnt, she's the one who begs to the go to the races... I will diffinately have to check out your sprint car races....

as for my codes and problems.. after an ALL NIGHT battery disconnect, when I got to work the engine light came on... so I pulled Key On codes and this time only got 91... thats good, though maybe the car wasnt running long enough to get the rest... but the light came on ... I did an ENGINE running test and got 91 as well... so maybe my O2 is messed... how do you know wich one it is?
-as

PKRWUD · 07-09-2003, 12:19 PM

41 and 42 are for the right side, and 91 and 92 are for the left side.

Your g/f sounds cool!

This is a huge picture, but it's one of my favorite because it looks like he just rolled forward, but notice there aren't aren't tire tracks in the dirt behind him (to the left). That's because he's actually going through the turns sideways. If it wasn't for the blur on the tires, you'd never even know the car was moving. 700 hp, N/A. You gotta love it!

Here's a link to the team website, if you're interested:

Jim Porter Racing

Take care,
~Chris

07-07-2003, 04:36 PM	#1
ChunkFunky Registered Member Join Date: Apr 2002 Location: Tustin, CA Posts: 465	EGR O2 Question ok, I had stock headers for a while and each side had a broken stud, so each side of teh H pipe had an exhaust leak. I finaly got new BBK headers in place and bolted it all up nice and I'm getting a check engine light after about 10-15 minutes of driving... I pulled codes and got 31, 41, 91... 31 is something with the EGR and the 41 and 91 are O2 leans... though not sure why there's TWO codes, unles it's one per side... this is the only mod I made...the only thing I can add is, one of the vacum lines on teh pass fender area that comes from that 4 way vacum distro and goes to the first valve on teh AIRPUMP tubing got melted. so I cant tell if it's sealed off and cauterised ...or leaking... eitherway... that's not an ENGINE vacum source anyway, is it?.. woudl that cause enough of a vaum leak? the tube is that hard plastic stuff.. i'll try to get a new one... but it just seems so miniscule to make these codes come up. though I cant imagine what else it could be, unless the EGR went bad coincidentaly... or the O2s are crapped up from having so much of an exhaust leak before them.. -as __________________ '89 GT Convertible: TFS TW Heads, TFS Street Intake, TFS Stage 1 Cam, FMS 1.6 RRs, 24# Injectors, Pro-M 75mm MAF, No Name CAI, 3.73s, O/R H-Pipe, FlowMasters, AOD w/ Trans-Go Shift Kit

07-08-2003, 08:01 AM	#2
PKRWUD Junior Member Join Date: Mar 1999 Location: Ventura, California Posts: 8,981	41 and 91 are your two O2 sensors. 31 means the EGR valve position sensor, that measures how much the EGR valve is opening, isn't working. You need to make sure that all the vacuum lines are functional, and attached. If that doesn't clear the code, then unplug the the harness at the sensor, and run a jumper wire between the orange/white wire and the brown/green wire, in the harness connector. Run KOEO self test again, and look for a code 35. Ignore all other codes. If code 35 comes up, remove the jumper and replace the sensor. The exhaust leak you had allowed extra air to enter the exhaust, and may have damaged the O2 sensors, but more than likely caused the ECM to learn a false setting. I would first try resetting the ECM, and then doing a relearn on it, and see if the O2 codes come back. If they do, you may have to replace them. Take care, ~Chris __________________ Webmaster: Rice Haters Club Jim Porter Racing Peckerwoods Pit Stop Support Your Local RED & WHITE!

07-08-2003, 08:40 AM	#3
ChunkFunky Registered Member Join Date: Apr 2002 Location: Tustin, CA Posts: 465	I did disconnect the battery for a while.. probabaly about 30 minutes.. that should be enought to reset it right? I'll try the code 35 test thing.. what would 35 signify? does this mean I'm running lean or just that the O2s seem to think so... I'm driving to CA on saturday and if I cant get this resolved by then will it be a problem? The cars drives fine.. but I dunno if I can get an EGR by then IF that's the problem.. I'll check the junk yards -as __________________ '89 GT Convertible: TFS TW Heads, TFS Street Intake, TFS Stage 1 Cam, FMS 1.6 RRs, 24# Injectors, Pro-M 75mm MAF, No Name CAI, 3.73s, O/R H-Pipe, FlowMasters, AOD w/ Trans-Go Shift Kit

07-08-2003, 01:30 PM	#4
PKRWUD Junior Member Join Date: Mar 1999 Location: Ventura, California Posts: 8,981	Yeah, 41 and 91 mean that the system is lean. 42 and 92 mean that the system is rich. Code 31 means that the EVP sensor signal voltage is below the minimum. Disconnecting it and jumping those two wires will send the VREF back to the ECM as the sensor signal voltage, which would be too high, and it will trip a code 35. If that happens, then you know the system is working, and the fault has to be in the sensor. Yes, 30 minutes should be long enough, but to be safe, do it again, but this time turn on the headlight switch after the battery is disconnected. This will ensure that the capacitors are completely drained, resetting the ECM. Driving it with the ECM thinking the system is lean will cause it to run rich. Running rich, across the country, will kill your wallet in the cost of gas, plus you run the high risk of clogging any cats that you might have. Take care, ~Chris __________________ Webmaster: Rice Haters Club Jim Porter Racing Peckerwoods Pit Stop Support Your Local RED & WHITE!

07-08-2003, 01:50 PM	#5
ChunkFunky Registered Member Join Date: Apr 2002 Location: Tustin, CA Posts: 465	Man... you are an quite an asset to the world... when I get out to California I'm going to buy you a beer or something.. or a keg.. or maybe a bottling plant... if I have any money left over from paying for gas... these codes were all in CONTINUOUS memory... and I got 11 for the KOEO test... I'll disconnect it again today and see what I come up with...it's a new code since the light comes on just about about 10 minutes.. wich is about warm up time I suppose... makes sense I guess.... I dont have to worry about my cats since I dont have any.. though I'll be getting a set when I get to CA... thanx for your help... for someone who doesnt even own a ford you sure have all the answers... I read somewhere you were an olds guy... I was an olds guy till I found out I was moving.. so I had to sell my 72 cutlass... it need alot of work, damn new england winters eat cars for breakfast... I hope to find a nice W-30 convertible when I get out there.. anyway... -as __________________ '89 GT Convertible: TFS TW Heads, TFS Street Intake, TFS Stage 1 Cam, FMS 1.6 RRs, 24# Injectors, Pro-M 75mm MAF, No Name CAI, 3.73s, O/R H-Pipe, FlowMasters, AOD w/ Trans-Go Shift Kit

07-08-2003, 02:08 PM	#6
PKRWUD Junior Member Join Date: Mar 1999 Location: Ventura, California Posts: 8,981	LOL! For the record, I have owned several Fords, including the F150 I drive now. It's a Mustang that I've never owned. I love Olds engines, and I love the older cars. I've got a 400ci out of a 1966 4-4-2 in my garage, waiting patiently for me to win the lottery so I can rebuild it. There are TONS of classics out here. They simply don't rust, and seem to last forever. If you want it, you'll be able to find it once you get here. Where abouts are you headed to? __________________ Webmaster: Rice Haters Club Jim Porter Racing Peckerwoods Pit Stop Support Your Local RED & WHITE!

07-08-2003, 08:29 PM	#7
ChunkFunky Registered Member Join Date: Apr 2002 Location: Tustin, CA Posts: 465	first the business.. then the BS... I it's 9:30 PM, I disconnected my battery... I will reconnect it before work tomarrow morning.. I turned on the HIGHLIGHT switch too.. that should do it... I'll drive to work and if the light comes on.. I will check my codes... if I get the 31, 41, 91 then I will do the jumper thing... if I get the 35, that means the sensor is bad...and I will go to the junk yard and get sensor... I actulay was there today and pulled that vacum harness from a grandmarquis.. it had the ford 5.0 I was going to snag that EGR but it looked different.. it didnt have a vacum line going to it for one... I'll have to find one that looks like mine I would imagine... or is it just the sensor part that needs to be replaced and not the WHOLE EGR unit... if that's the case will this other one work? ok... and here's the rest of my boring story... I'm moving to IRVINE, cause that's where my girlfriend is going to school.... though I bet we'll end up living in costa mesa or tustin or something like that due to cheaper rents and such.. I wont have a job when I get out there .. so I hope I can find one doing what I normaly do.. network administrator stuff... though I suppose worst case I could fix cars or something.... I've never been a big fan of these computer controlled cars.... but my heart is in the old muscle... and oldsmobiles particularly... my plan was to take this 72 cutlass and drop in a 455 but since I'm moving, I sold it... I hope I can find one out there and do it up nice... I like the 71-72 body style.... or the 67 wich is a different look... I didnt like the front ends of the 68-70s as much... but I suppose this is all for another forum. Ventura isnt FAR I see though not aroudn the corner either... are there alot of dragways out there? I have yet to bring the mustang to the track... -as __________________ '89 GT Convertible: TFS TW Heads, TFS Street Intake, TFS Stage 1 Cam, FMS 1.6 RRs, 24# Injectors, Pro-M 75mm MAF, No Name CAI, 3.73s, O/R H-Pipe, FlowMasters, AOD w/ Trans-Go Shift Kit Last edited by ChunkFunky; 07-08-2003 at 08:39 PM..

07-09-2003, 02:12 AM	#8
PKRWUD Junior Member Join Date: Mar 1999 Location: Ventura, California Posts: 8,981	Some EGR valves have the EVP sensor mounted to them, and some are separate. get the same kind that you have. Carlsbad is a cute little drag strip that's not very far from Irvine/Costa Mesa. Pomona is close, too. Other than that, there's Palmdale, in the high desert, but that's pretty far. That's where FFW is going to be in the fall. Ventura is a good 2+ hour drive from Irvine, depending on traffic. Maybe you and your girlfriend can come up to one of our Sprint car races, and hang out in the pits. Take care, ~Chris __________________ Webmaster: Rice Haters Club Jim Porter Racing Peckerwoods Pit Stop Support Your Local RED & WHITE!

07-09-2003, 06:09 AM	#9
ChunkFunky Registered Member Join Date: Apr 2002 Location: Tustin, CA Posts: 465	as strange as it may be, my girlfriend enjoys this car stuff.. where most girls wouldnt, she's the one who begs to the go to the races... I will diffinately have to check out your sprint car races.... as for my codes and problems.. after an ALL NIGHT battery disconnect, when I got to work the engine light came on... so I pulled Key On codes and this time only got 91... thats good, though maybe the car wasnt running long enough to get the rest... but the light came on ... I did an ENGINE running test and got 91 as well... so maybe my O2 is messed... how do you know wich one it is? -as __________________ '89 GT Convertible: TFS TW Heads, TFS Street Intake, TFS Stage 1 Cam, FMS 1.6 RRs, 24# Injectors, Pro-M 75mm MAF, No Name CAI, 3.73s, O/R H-Pipe, FlowMasters, AOD w/ Trans-Go Shift Kit

07-09-2003, 12:19 PM	#10
PKRWUD Junior Member Join Date: Mar 1999 Location: Ventura, California Posts: 8,981	41 and 42 are for the right side, and 91 and 92 are for the left side. Your g/f sounds cool! This is a huge picture, but it's one of my favorite because it looks like he just rolled forward, but notice there aren't aren't tire tracks in the dirt behind him (to the left). That's because he's actually going through the turns sideways. If it wasn't for the blur on the tires, you'd never even know the car was moving. 700 hp, N/A. You gotta love it! Here's a link to the team website, if you're interested: Jim Porter Racing Take care, ~Chris __________________ Webmaster: Rice Haters Club Jim Porter Racing Peckerwoods Pit Stop Support Your Local RED & WHITE!

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