Ongoing saga
Thread Starter
Melting Slicks
Joined: Feb 2005
Posts: 2,135
Likes: 0
From: Sebastian Florida
St. Jude Donor '06
Ongoing saga
My 93 w/headers runs rich, I have heated o2's.
Replaced FI's and regulator, changed plugs and car started up real quick and then got harder and harder to start.
Just replaced opti a couple of months ago when the radiator left town, I have a Datamaster run and the o2's seem to be all over the place on one and the other is fairly flat, all this is at idle which is 625 and fuel trim of 16.
On the Datamaster the Cloop fuel tmr and fuel enabled are 1 and all the others are 0, spark advance is 25, IAC pos. is 89, BPW mS is 2.25 and 2.35.
Sorry to be long winded, but this is driving me nuts. Idle is high, but I cannot find a vacuum leak.
Replaced FI's and regulator, changed plugs and car started up real quick and then got harder and harder to start.
Just replaced opti a couple of months ago when the radiator left town, I have a Datamaster run and the o2's seem to be all over the place on one and the other is fairly flat, all this is at idle which is 625 and fuel trim of 16.
On the Datamaster the Cloop fuel tmr and fuel enabled are 1 and all the others are 0, spark advance is 25, IAC pos. is 89, BPW mS is 2.25 and 2.35.
Sorry to be long winded, but this is driving me nuts. Idle is high, but I cannot find a vacuum leak.
Last edited by Randy93; Mar 10, 2009 at 12:53 PM.
Le Mans Master
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From: Akron Ohio
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St. Jude Donor '09-'10-'11
The reduced back pressure of headers will make the car run rich without a proper tune. Did you change the chip or have it tuned?
Le Mans Master
Joined: Feb 2005
Posts: 5,146
Likes: 3
From: The Motor City
My 93 w/headers runs rich, I have heated o2's.
Replaced FI's and regulator, changed plugs and car started up real quick and then got harder and harder to start.
Just replaced opti a couple of months ago when the radiator left town, I have a Datamaster run and the o2's seem to be all over the place on one and the other is fairly flat, all this is at idle which is 625 and fuel trim of 16.
On the Datamaster the Cloop fuel tmr and fuel enabled are 1 and all the others are 0, spark advance is 25, IAC pos. is 89, BPW mS is 2.25 and 2.35.
Sorry to be long winded, but this is driving me nuts. Idle is high, but I cannot find a vacuum leak.
Replaced FI's and regulator, changed plugs and car started up real quick and then got harder and harder to start.
Just replaced opti a couple of months ago when the radiator left town, I have a Datamaster run and the o2's seem to be all over the place on one and the other is fairly flat, all this is at idle which is 625 and fuel trim of 16.
On the Datamaster the Cloop fuel tmr and fuel enabled are 1 and all the others are 0, spark advance is 25, IAC pos. is 89, BPW mS is 2.25 and 2.35.
Sorry to be long winded, but this is driving me nuts. Idle is high, but I cannot find a vacuum leak.
where are the two 02's loacted ? does the one that is faily flat respond when actually driving?
iac sounds a tad high if at operating temp (C.L.) I would want it around 40 (open throttle blade more).
what rpm does it idle at ?
what is the fuel pressure set at ?
w/out tuning the only other option would be to reduce FP....until you can get the fueling in the tune right.
Last edited by mseven; Mar 11, 2009 at 07:27 PM.
Thread Starter
Melting Slicks
Joined: Feb 2005
Posts: 2,135
Likes: 0
From: Sebastian Florida
St. Jude Donor '06
Car idles at 625, temp was 176 and the o2's are located in the collector.
Car has a stock regulator and I forgot 1 detail, it has Bosch 24lb blue tops that Jon from FIC says are matched to stock.
Headers should not make the car run this rich, have had headers on several cars and did not have this problem.
Could the IAC be off and the ECM is correcting by adding more fuel?
Car has a stock regulator and I forgot 1 detail, it has Bosch 24lb blue tops that Jon from FIC says are matched to stock.
Headers should not make the car run this rich, have had headers on several cars and did not have this problem.
Could the IAC be off and the ECM is correcting by adding more fuel?
Le Mans Master
Joined: Feb 1999
Posts: 9,913
Likes: 37
From: South Carolina
St. Jude Donor '03 & '05
Randy, on our speed density cars, long tube headers do make us run richer. Why? Because the O2 see more air and think, she is running lean, dump more fuel to establish correct AF ratio.
I went from shorty SLPS, gutted cats, to Long Tubes and it needed a retune, on my 93.
Couple questions. What camshaft? What tune do you have right now?
Also, can you send me the datamster file. I will compare it idleing etc to a stock 93, a 93 w/Hot cam and mine with 396 Hot Cam and Long tubes.
Currently I have more cam, but I have files somewhere showing different stages.
If one of your O2's isnt doing anything, check and ensure she is grounded well and has a good constant power source. Remember, its only .1 volts, not much and it doesnt take much for it to be a bad connection.
MSEVEN is correct on checking things out, leaks etc. I had a bad one with no codes, and I run heated also.
Also, how does your idle react cold/hot with and without AC?
I went from shorty SLPS, gutted cats, to Long Tubes and it needed a retune, on my 93.
Couple questions. What camshaft? What tune do you have right now?
Also, can you send me the datamster file. I will compare it idleing etc to a stock 93, a 93 w/Hot cam and mine with 396 Hot Cam and Long tubes.
Currently I have more cam, but I have files somewhere showing different stages.
If one of your O2's isnt doing anything, check and ensure she is grounded well and has a good constant power source. Remember, its only .1 volts, not much and it doesnt take much for it to be a bad connection.
MSEVEN is correct on checking things out, leaks etc. I had a bad one with no codes, and I run heated also.
Also, how does your idle react cold/hot with and without AC?
Last edited by steve40th; Mar 11, 2009 at 07:42 PM.
Le Mans Master
Joined: Feb 2005
Posts: 5,146
Likes: 3
From: The Motor City
Car idles at 625, temp was 176 and the o2's are located in the collector.
Car has a stock regulator and I forgot 1 detail, it has Bosch 24lb blue tops that Jon from FIC says are matched to stock.
Headers should not make the car run this rich, have had headers on several cars and did not have this problem.
Could the IAC be off and the ECM is correcting by adding more fuel?
Car has a stock regulator and I forgot 1 detail, it has Bosch 24lb blue tops that Jon from FIC says are matched to stock.
Headers should not make the car run this rich, have had headers on several cars and did not have this problem.
Could the IAC be off and the ECM is correcting by adding more fuel?
At 80+ cts. (@ operating temp. c.l.) that is having the throttle blade closed a bit, I just don't believe that would be the entire cause for rich condition. Have you looked at where is the fuel pressure at ? Was the tune/car originally set up for a 24 # inj.?
it would also be imprtant to know if the other 02 responds properly under normal driving. (.550mv is the crossover point so .650mv is not really rich).
Basically from what you are saying it's also sounding like Jon may have to tame those down for you unless you can tweak the tune.
Last edited by mseven; Mar 11, 2009 at 07:54 PM.
Le Mans Master
Joined: Feb 1999
Posts: 9,913
Likes: 37
From: South Carolina
St. Jude Donor '03 & '05
Also, just ot check, make sure your IAC is good too. Even though you see counts within datamster, those counts are only what the ECM is telling the IAC to do. The actual counts never make it to Datamster.
And you wont get a code for IAC as there is none.
http://shbox.com/1/iac2.jpg
And you wont get a code for IAC as there is none.
http://shbox.com/1/iac2.jpg
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Thread Starter
Melting Slicks
Joined: Feb 2005
Posts: 2,135
Likes: 0
From: Sebastian Florida
St. Jude Donor '06
Ok, I got the tune from PCMforless and it was for FMS 24#. Which I got rid of, the one o2 does not stay a constant value(sorry), it does move up and down some. I have searched high and low for leaks and have found none(doesn't mean there isnt and I will check somemore), the IAC is only about a year and half old. Had to replace it when I accidently stepped on it while cleaning the TB. Cam is a very mild cam, do not know the specs , as the previous owner installed.
I do have the datamaster and I will GLADLY send it to you.
Car started running rich just before I put the headers on, thought it just needed a tuneup.
Have not checked FP, gauge is busted and havent bought a new one yet. Have headers, hiflow cats, cam and stock back and will check the o2 connections again.
THANKS ALL!!!!
I do have the datamaster and I will GLADLY send it to you.
Car started running rich just before I put the headers on, thought it just needed a tuneup.
Have not checked FP, gauge is busted and havent bought a new one yet. Have headers, hiflow cats, cam and stock back and will check the o2 connections again.
THANKS ALL!!!!
Le Mans Master
Joined: Feb 1999
Posts: 9,913
Likes: 37
From: South Carolina
St. Jude Donor '03 & '05
Ok, I got the tune from PCMforless and it was for FMS 24#. Which I got rid of, the one o2 does not stay a constant value(sorry), it does move up and down some. I have searched high and low for leaks and have found none(doesn't mean there isnt and I will check somemore), the IAC is only about a year and half old. Had to replace it when I accidently stepped on it while cleaning the TB. Cam is a very mild cam, do not know the specs , as the previous owner installed.
I do have the datamaster and I will GLADLY send it to you.
Car started running rich just before I put the headers on, thought it just needed a tuneup.
Have not checked FP, gauge is busted and havent bought a new one yet. Have headers, hiflow cats, cam and stock back and will check the o2 connections again.
THANKS ALL!!!!
I do have the datamaster and I will GLADLY send it to you.
Car started running rich just before I put the headers on, thought it just needed a tuneup.
Have not checked FP, gauge is busted and havent bought a new one yet. Have headers, hiflow cats, cam and stock back and will check the o2 connections again.
THANKS ALL!!!!
I will look and see if I have a lng tube header tune. Alvin will fix it for you I am sure, if need be.
Supporting Vendor
Joined: Mar 2008
Posts: 1,762
Likes: 14
From: Cumming Ga
Ok, I got the tune from PCMforless and it was for FMS 24#. Which I got rid of, the one o2 does not stay a constant value(sorry), it does move up and down some. I have searched high and low for leaks and have found none(doesn't mean there isnt and I will check somemore), the IAC is only about a year and half old. Had to replace it when I accidently stepped on it while cleaning the TB. Cam is a very mild cam, do not know the specs , as the previous owner installed.
I do have the datamaster and I will GLADLY send it to you.
Car started running rich just before I put the headers on, thought it just needed a tuneup.
Have not checked FP, gauge is busted and havent bought a new one yet. Have headers, hiflow cats, cam and stock back and will check the o2 connections again.
THANKS ALL!!!!
I do have the datamaster and I will GLADLY send it to you.
Car started running rich just before I put the headers on, thought it just needed a tuneup.
Have not checked FP, gauge is busted and havent bought a new one yet. Have headers, hiflow cats, cam and stock back and will check the o2 connections again.
THANKS ALL!!!!
Jon
Supporting Vendor
Joined: Mar 2008
Posts: 1,762
Likes: 14
From: Cumming Ga
Thread Starter
Melting Slicks
Joined: Feb 2005
Posts: 2,135
Likes: 0
From: Sebastian Florida
St. Jude Donor '06
Ok, I have some more info. Cleaned TB and reset IAC and now the IAC count is 127. Second, in neutral the car starts busting up about 3100 rpm's and is now running rough again.
Going on Jon's suggestion, does anybody know if Advance or anyone test coils?
Also, the TPS is reading .75 and should be around .54, can anything cause this to be this high other than a bad TPS?
Going on Jon's suggestion, does anybody know if Advance or anyone test coils?
Also, the TPS is reading .75 and should be around .54, can anything cause this to be this high other than a bad TPS?
Le Mans Master
Joined: Feb 1999
Posts: 9,913
Likes: 37
From: South Carolina
St. Jude Donor '03 & '05
Ok, I have some more info. Cleaned TB and reset IAC and now the IAC count is 127. Second, in neutral the car starts busting up about 3100 rpm's and is now running rough again.
Going on Jon's suggestion, does anybody know if Advance or anyone test coils?
Also, the TPS is reading .75 and should be around .54, can anything cause this to be this high other than a bad TPS?
Going on Jon's suggestion, does anybody know if Advance or anyone test coils?
Also, the TPS is reading .75 and should be around .54, can anything cause this to be this high other than a bad TPS?
Le Mans Master
Joined: Jul 2007
Posts: 5,043
Likes: 7
From: Tampa Florida
Ok, I have some more info. Cleaned TB and reset IAC and now the IAC count is 127. Second, in neutral the car starts busting up about 3100 rpm's and is now running rough again.
Going on Jon's suggestion, does anybody know if Advance or anyone test coils?
Also, the TPS is reading .75 and should be around .54, can anything cause this to be this high other than a bad TPS?
Going on Jon's suggestion, does anybody know if Advance or anyone test coils?
Also, the TPS is reading .75 and should be around .54, can anything cause this to be this high other than a bad TPS?
There was a thread "just the other day" about how people are slotting out the mounting holes on the the TPS sensor to attempt to trick/adjust the voltage setting closer to the .54 setting.....this setting which is normally only controlled by the ECM/PCM.
Le Mans Master
Joined: Feb 1999
Posts: 9,913
Likes: 37
From: South Carolina
St. Jude Donor '03 & '05
The autoparts stores won't test the coils....you can check the resistance (ohm) across the coil and compare your value to someone else's to see if yours is close.
There was a thread "just the other day" about how people are slotting out the mounting holes on the the TPS sensor to attempt to trick/adjust the voltage setting closer to the .54 setting.....this setting which is normally only controlled by the ECM/PCM.
There was a thread "just the other day" about how people are slotting out the mounting holes on the the TPS sensor to attempt to trick/adjust the voltage setting closer to the .54 setting.....this setting which is normally only controlled by the ECM/PCM.
Thread Starter
Melting Slicks
Joined: Feb 2005
Posts: 2,135
Likes: 0
From: Sebastian Florida
St. Jude Donor '06
Blades are completely closed, I checked that. Jon suggested making the hole bigger, going to try that this weekend.
Just curious what is making the car start busting up, but I am going work on the TPS and the IAC first and then go from there.
Thanks guys!!
Just curious what is making the car start busting up, but I am going work on the TPS and the IAC first and then go from there.
Thanks guys!!