Official SHARKTUNER thread
02-25-2008, 05:42 AM
#211
Rennlist Member
Greetings,
I have a question to pose to the group to see if anyone has come across this situation....
We have a RMT on a 1988 S4 running at 5lbs boost....it has had a previous hot start issue and Chuck has been methodically changing out parts....including the idle stabilizer and the throttle position switch.
He cold starts and the car runs fine....stops and upon restart, cannot get it to behave....after about 2-3 minutes of pedal fluttering, it sorts itself out and off he goes.
We had Thurston install a WBO2 sensor for sharktuning at the dyno session on Saturday.....one of the issues that the ST indicated was the TPS on the monitoring page....at idle it indicated "WOT", while cruising down the highway, it remained in "WOT" and upon acceleration the indicator moved to "Cruise" on the map.....we are going to pull it apart and do the usual checks, but I wanted to see if there was any other experience out there.....it seems like two wires are crossed, but can't imagine how....what are the typical failure modes for the TPS?....
comments?
I have a question to pose to the group to see if anyone has come across this situation....
We have a RMT on a 1988 S4 running at 5lbs boost....it has had a previous hot start issue and Chuck has been methodically changing out parts....including the idle stabilizer and the throttle position switch.
He cold starts and the car runs fine....stops and upon restart, cannot get it to behave....after about 2-3 minutes of pedal fluttering, it sorts itself out and off he goes.
We had Thurston install a WBO2 sensor for sharktuning at the dyno session on Saturday.....one of the issues that the ST indicated was the TPS on the monitoring page....at idle it indicated "WOT", while cruising down the highway, it remained in "WOT" and upon acceleration the indicator moved to "Cruise" on the map.....we are going to pull it apart and do the usual checks, but I wanted to see if there was any other experience out there.....it seems like two wires are crossed, but can't imagine how....what are the typical failure modes for the TPS?....
comments?
It is difficult to see how a TPS can produce the result you seem to get, even with incorrect wiring.
Before you rip the intake off, check at the LH 35way connector that the ilde and WOT switches are doing what they should there with an ohmeter.
I have to warn you that one symptom of impending total LH ECU failure can be nonsense indications of WOT and idle switches.
So please check first the switches at 35way connector with an ohmeter, if they are OK, then borrow another LH ECU and try again with the ST.
Let me know.
02-25-2008, 12:51 PM
#213
Under the Lift
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Greetings,
I have a question to pose to the group to see if anyone has come across this situation....
We have a RMT on a 1988 S4 running at 5lbs boost....it has had a previous hot start issue and Chuck has been methodically changing out parts....including the idle stabilizer and the throttle position switch.
He cold starts and the car runs fine....stops and upon restart, cannot get it to behave....after about 2-3 minutes of pedal fluttering, it sorts itself out and off he goes.
We had Thurston install a WBO2 sensor for sharktuning at the dyno session on Saturday.....one of the issues that the ST indicated was the TPS on the monitoring page....at idle it indicated "WOT", while cruising down the highway, it remained in "WOT" and upon acceleration the indicator moved to "Cruise" on the map.....we are going to pull it apart and do the usual checks, but I wanted to see if there was any other experience out there.....it seems like two wires are crossed, but can't imagine how....what are the typical failure modes for the TPS?....
comments?
I have a question to pose to the group to see if anyone has come across this situation....
We have a RMT on a 1988 S4 running at 5lbs boost....it has had a previous hot start issue and Chuck has been methodically changing out parts....including the idle stabilizer and the throttle position switch.
He cold starts and the car runs fine....stops and upon restart, cannot get it to behave....after about 2-3 minutes of pedal fluttering, it sorts itself out and off he goes.
We had Thurston install a WBO2 sensor for sharktuning at the dyno session on Saturday.....one of the issues that the ST indicated was the TPS on the monitoring page....at idle it indicated "WOT", while cruising down the highway, it remained in "WOT" and upon acceleration the indicator moved to "Cruise" on the map.....we are going to pull it apart and do the usual checks, but I wanted to see if there was any other experience out there.....it seems like two wires are crossed, but can't imagine how....what are the typical failure modes for the TPS?....
comments?
02-25-2008, 02:29 PM
#214
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Thanks,
This was happening before we changed out the 19#'s to 24#'s to now 30#'s for the rear mount turbo set-up.....
I am going to poke a spare brain in it first and then we'll start to chase down the plugs.
jt
This was happening before we changed out the 19#'s to 24#'s to now 30#'s for the rear mount turbo set-up.....
I am going to poke a spare brain in it first and then we'll start to chase down the plugs.
jt
03-05-2008, 05:35 PM
#215
Rennlist Member
Well, I finally got around to buring a chip. Is everyone using the EPROMS from Digi-key?
Has anyone experienced a bad chip (i.e., starting off good but went bad)?
What's the longest anyone has driven with a DIY burned chip?
Has anyone experienced a bad chip (i.e., starting off good but went bad)?
What's the longest anyone has driven with a DIY burned chip?
03-05-2008, 06:14 PM
#217
Supercharged
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If you are using "used" EPROMS they can only be erased so many times, in which case you need to chuck them. Also I believe the 85/86 cars can only take one kind of EPROM, but I don't recall what format. 27C256x12ms?
Is your chip burner verifying the burn? And are you sure you have the correct chip selected int he chip burner software?
Is your chip burner verifying the burn? And are you sure you have the correct chip selected int he chip burner software?
03-05-2008, 09:57 PM
#218
Rennlist Member
Everything went well with the burn and it was verified good. I was just curious if anyone has experienced problems with their EPROMs?
I think 85 and up use the same EPROM's 256KBIT UV 120NS 28FDIP.
I think 85 and up use the same EPROM's 256KBIT UV 120NS 28FDIP.
03-06-2008, 12:43 AM
#219
Three Wheelin'
Darien,
I believe the '85/'86 uses a 4k 24 pin 2732 EPROM. '87 and later uses the 27C256 28 pin EPROM. John Speake has an adapter that allows use of the 27C256 chip in the 2732 24 pin socket.
Louie
I believe the '85/'86 uses a 4k 24 pin 2732 EPROM. '87 and later uses the 27C256 28 pin EPROM. John Speake has an adapter that allows use of the 27C256 chip in the 2732 24 pin socket.
Louie
03-06-2008, 05:04 AM
#220
Rennlist Member
Hi Louie,
Hmm, I'm using the 27C256 28 pin EPROM with the adaptor supplied by John.
Any idea if there's any downfall to keep it as is? Will the adaptor cause any loss of current?
Hmm, I'm using the 27C256 28 pin EPROM with the adaptor supplied by John.
Any idea if there's any downfall to keep it as is? Will the adaptor cause any loss of current?
03-06-2008, 06:56 AM
#221
Rennlist Member
Louie is correct - 85/86 use 2732A and >87 use 27C256
Adaptor is fine, no probs when you save the file as 27C256 with SharkTuner and use the adaptor.
I buy my 2732A from Futurlec, some of them do not program on first try. But reliable once programmed and in use.
Adaptor is fine, no probs when you save the file as 27C256 with SharkTuner and use the adaptor.
I buy my 2732A from Futurlec, some of them do not program on first try. But reliable once programmed and in use.
03-12-2008, 02:12 PM
#222
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I installed 42lb injectors in my car the other day and a SuperMAF from John.
Got the car started fine and sharktuned quite a bit at cruise and idle.
Question 1.
When we auto tune at idle the ST keeps the idle perfect, hovering around 14ish to 15ish. The car really idles nice, as nice as it ever has actually. The gremlin we have (and Darien has encountered it also) is when we stop the autotune at idle, the engine after about 3-4 secs, stumbles a bit, then begins to run noticable rougher. The AFR jumps up to tthe high 16-17s
I thought the the ST had already "autotuned" the cells in the maps and it should run/idel just as smooth as it did during the autotune.
#2) The Super MAF. We Data logged a run and the voltage still caps out at around 5.1ish volts IRRC. I have hooked my own voltmeter to the MAF wires in the past and i know it goes WAY higher than that under boost. I thought the Super MAF was able to meaure above and beyond 5.0-5.1v?...or is there some wizardry going on here where it is measuring above 5.1v but only showing 5.1 in the datalog.
IRRC the LH doesnt knwo what to do with anyhting in excess of appx 5.1volts anyway. I just want to make sure things are working OK before i start putting the hammer down on some WOT tuning.
This really is the Holly Grail of Tuning for our cars. Slicker than snot!
Remember. If you inadvertantly FLOOD the car, the best way to get it running is pull the fuel pump relay and crank it with your foot to the floor until it catches and then "fires" no more. Stop, put the relay back in and start normally..
Got the car started fine and sharktuned quite a bit at cruise and idle.
Question 1.
When we auto tune at idle the ST keeps the idle perfect, hovering around 14ish to 15ish. The car really idles nice, as nice as it ever has actually. The gremlin we have (and Darien has encountered it also) is when we stop the autotune at idle, the engine after about 3-4 secs, stumbles a bit, then begins to run noticable rougher. The AFR jumps up to tthe high 16-17s
I thought the the ST had already "autotuned" the cells in the maps and it should run/idel just as smooth as it did during the autotune.
#2) The Super MAF. We Data logged a run and the voltage still caps out at around 5.1ish volts IRRC. I have hooked my own voltmeter to the MAF wires in the past and i know it goes WAY higher than that under boost. I thought the Super MAF was able to meaure above and beyond 5.0-5.1v?...or is there some wizardry going on here where it is measuring above 5.1v but only showing 5.1 in the datalog.
IRRC the LH doesnt knwo what to do with anyhting in excess of appx 5.1volts anyway. I just want to make sure things are working OK before i start putting the hammer down on some WOT tuning.
This really is the Holly Grail of Tuning for our cars. Slicker than snot!
Remember. If you inadvertantly FLOOD the car, the best way to get it running is pull the fuel pump relay and crank it with your foot to the floor until it catches and then "fires" no more. Stop, put the relay back in and start normally..
03-12-2008, 02:42 PM
#223
Rennlist Member
Hello Tony
Q1. I think the answer is that the ST Autotunes disables the O2 loop when tuning, otherwise the two would fight each other. When you come off Autotune, the LH adaptation comes into play. I think after you drive a few miles everything will settle down again.
Q2. 5.1v with a SuperMAF coresponds to 6.1v out of a stock MAF.
The LH can cope with voltages higher than 5.1v, up to 6v.
6v out of a SM is equiv to over 7v out of a stock MAF !
The MAF law of volts vs air mass is a log law i.e quite compressed at the high flow end.
Q1. I think the answer is that the ST Autotunes disables the O2 loop when tuning, otherwise the two would fight each other. When you come off Autotune, the LH adaptation comes into play. I think after you drive a few miles everything will settle down again.
Q2. 5.1v with a SuperMAF coresponds to 6.1v out of a stock MAF.
The LH can cope with voltages higher than 5.1v, up to 6v.
6v out of a SM is equiv to over 7v out of a stock MAF !
The MAF law of volts vs air mass is a log law i.e quite compressed at the high flow end.
03-12-2008, 03:03 PM
#224
Three Wheelin'
Tony,
Reference question 1: what are you using for your NB input to the ST? If a regular NB sensor, then guess I don't have a great answer. If you are using a NB simulated output from your WB, then check the NB simulated output calibration. If your NB sim output is biased toward the rich side, then closed loop will lean the mixture out (trying to reach what it thinks is 14.7 AFR) and that will be read lean correctly from the WB input to the ST.
Louie
Reference question 1: what are you using for your NB input to the ST? If a regular NB sensor, then guess I don't have a great answer. If you are using a NB simulated output from your WB, then check the NB simulated output calibration. If your NB sim output is biased toward the rich side, then closed loop will lean the mixture out (trying to reach what it thinks is 14.7 AFR) and that will be read lean correctly from the WB input to the ST.
Louie
I installed 42lb injectors in my car the other day and a SuperMAF from John.
Got the car started fine and sharktuned quite a bit at cruise and idle.
Question 1.
When we auto tune at idle the ST keeps the idle perfect, hovering around 14ish to 15ish. The car really idles nice, as nice as it ever has actually. The gremlin we have (and Darien has encountered it also) is when we stop the autotune at idle, the engine after about 3-4 secs, stumbles a bit, then begins to run noticable rougher. The AFR jumps up to tthe high 16-17s
I thought the the ST had already "autotuned" the cells in the maps and it should run/idel just as smooth as it did during the autotune.
<snip>
This really is the Holly Grail of Tuning for our cars. Slicker than snot!
Remember. If you inadvertantly FLOOD the car, the best way to get it running is pull the fuel pump relay and crank it with your foot to the floor until it catches and then "fires" no more. Stop, put the relay back in and start normally..
Got the car started fine and sharktuned quite a bit at cruise and idle.
Question 1.
When we auto tune at idle the ST keeps the idle perfect, hovering around 14ish to 15ish. The car really idles nice, as nice as it ever has actually. The gremlin we have (and Darien has encountered it also) is when we stop the autotune at idle, the engine after about 3-4 secs, stumbles a bit, then begins to run noticable rougher. The AFR jumps up to tthe high 16-17s
I thought the the ST had already "autotuned" the cells in the maps and it should run/idel just as smooth as it did during the autotune.
<snip>
This really is the Holly Grail of Tuning for our cars. Slicker than snot!
Remember. If you inadvertantly FLOOD the car, the best way to get it running is pull the fuel pump relay and crank it with your foot to the floor until it catches and then "fires" no more. Stop, put the relay back in and start normally..
03-12-2008, 04:37 PM
#225
Rennlist Member
Hi Louie,
Tony would be feeding his WB input to the ST, and I'm assuming he is reporting the A/F as indicated by the ST. If he is using a simulated NB with an LMA3 (?) data logging, then that may have the issue you mention.
Tony would be feeding his WB input to the ST, and I'm assuming he is reporting the A/F as indicated by the ST. If he is using a simulated NB with an LMA3 (?) data logging, then that may have the issue you mention.