Very strange hesitation... happens at exactly the same time, everytime.
10-09-04, 08:09 PM
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Very strange hesitation... happens at exactly the same time, everytime.
Ok, this is getting pretty annoying, but it could be worse.
I'm going to let you know that how long the engine has been running, the temp (cold, or normal oper. temps) has no effect on this. Neither does driving it "hard" or babying it.
After my clock reads 1:17-1:25, all of a sudden the car will make almos no power, I can only press the throttle a TINY bit (right when the secondary plates start to open.. you can feel it in the pedal) just enough to pull over, WILL NOT go over 3K, and cant go past 2nd gear.
All I have to do is take off the neg batt terminal, wait about a minute, and start he back up and it does this all over again.
No ECU codes, only codes it throws are emissions.
This is definately computer related... has to be. No hoses are coming un-done, and the fact that it happens within the same window of time is very strange.
The only thing I know to do right now is start by replacing the ECU... all the sensors test out ok.
I have searched, but I dont know how to narrow it down from just "hesitation" or what not... all I get are 3800 rpm hesitations, and others.
When it runs good, it pulls great all the way to 7-8K. Only thing I can tell you is that the airpump is just pumping to atmosphere at the moment (waiting on a dual alt pulley), the 6 ports are wired open, and VDI is disabled.
Any help appreciated,
Jon
I'm going to let you know that how long the engine has been running, the temp (cold, or normal oper. temps) has no effect on this. Neither does driving it "hard" or babying it.
After my clock reads 1:17-1:25, all of a sudden the car will make almos no power, I can only press the throttle a TINY bit (right when the secondary plates start to open.. you can feel it in the pedal) just enough to pull over, WILL NOT go over 3K, and cant go past 2nd gear.
All I have to do is take off the neg batt terminal, wait about a minute, and start he back up and it does this all over again.
No ECU codes, only codes it throws are emissions.
This is definately computer related... has to be. No hoses are coming un-done, and the fact that it happens within the same window of time is very strange.
The only thing I know to do right now is start by replacing the ECU... all the sensors test out ok.
I have searched, but I dont know how to narrow it down from just "hesitation" or what not... all I get are 3800 rpm hesitations, and others.
When it runs good, it pulls great all the way to 7-8K. Only thing I can tell you is that the airpump is just pumping to atmosphere at the moment (waiting on a dual alt pulley), the 6 ports are wired open, and VDI is disabled.
Any help appreciated,
Jon
Last edited by poor_red_neck; 10-09-04 at 08:30 PM.
10-09-04, 08:42 PM
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Did you check your cats (if you have them?) I know you say no airpump, if you left the cat there without the pump it could clog, which will cause hesitation
10-09-04, 09:26 PM
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well, I doubt it really has much to do with the cat. Yah there is no air going to it... but its a new bonez, and I mean it pulls perfectly for not having VDI, just at that point in time... boom.
I would like to see if POSSIBLY it is the TPS, however, I'm not driving w/o the tps again... 4 ******* miles to the gallon, BAH! The car drives fine with it plugged in. Fullrange is perfect (reads fine on AFC) and AFAIK, the narror range is good.
I thought maybe the AFM wire is ******* up, or some other wire is coming loose, but I tried driving around on very bumpy roads to see if that shakes something loose consistantly, no go.
I have done grounding work, so I dont think that could be it. Doesn't seem like a secondary injector thing either, as those dont come online until 3800... this is a wall at 3K. Not the BAC valve, as that's useless after Idle.
I'm currently on the look for a new ECU
Man, more ******* cash. God I love it!!!!
It's not the water thermo sensor, because it stays plugged in... and I don't mess with ANY wires, except unplugging the negative battery terminal.
It's not timing, as it runs fine until this point in time basicly.
There was something else on my mind I was going to rule out, but I forgot.
I would like to see if POSSIBLY it is the TPS, however, I'm not driving w/o the tps again... 4 ******* miles to the gallon, BAH! The car drives fine with it plugged in. Fullrange is perfect (reads fine on AFC) and AFAIK, the narror range is good.
I thought maybe the AFM wire is ******* up, or some other wire is coming loose, but I tried driving around on very bumpy roads to see if that shakes something loose consistantly, no go.
I have done grounding work, so I dont think that could be it. Doesn't seem like a secondary injector thing either, as those dont come online until 3800... this is a wall at 3K. Not the BAC valve, as that's useless after Idle.
I'm currently on the look for a new ECU
Man, more ******* cash. God I love it!!!!
It's not the water thermo sensor, because it stays plugged in... and I don't mess with ANY wires, except unplugging the negative battery terminal.
It's not timing, as it runs fine until this point in time basicly.
There was something else on my mind I was going to rule out, but I forgot.
Last edited by poor_red_neck; 10-09-04 at 09:31 PM.
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10-09-04, 10:03 PM
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ECU's don't have internal clocks- do they???
You ARE talking about the clock in the warning panel, right?
Take the plug off of the clock/warning panel, lol...
You ARE talking about the clock in the warning panel, right?
Take the plug off of the clock/warning panel, lol...
10-09-04, 10:19 PM
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Originally Posted by poor_red_neck
After my clock reads 1:17-1:25, all of a sudden the car will make almos no power, I can only press the throttle a TINY bit (right when the secondary plates start to open.. you can feel it in the pedal) just enough to pull over, WILL NOT go over 3K, and cant go past 2nd gear.
All I have to do is take off the neg batt terminal, wait about a minute, and start he back up and it does this all over again.
Have you checked your secondary injectors?
10-10-04, 08:33 AM
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Ok guys... the CLOCK has NOTHING to do with this.
I'm simply stating that this happens 17 MINUTES-25 MINUTES AFTER ECU resetting.
The only reason I said 1:17 etc is because as posted above... the clock resets to 1:00am after you take off the neg batt terminal.
The secondaries are fine. 13 ohms. resistance. Plus, those dont come on til 3800, not 3000.
Any other time (before ECU resetting) like I said, pulls fine all the way up the rev meter.
So looks like replacing the ECU is my only hope?
Shitty.
I'm simply stating that this happens 17 MINUTES-25 MINUTES AFTER ECU resetting.
The only reason I said 1:17 etc is because as posted above... the clock resets to 1:00am after you take off the neg batt terminal.
The secondaries are fine. 13 ohms. resistance. Plus, those dont come on til 3800, not 3000.
Any other time (before ECU resetting) like I said, pulls fine all the way up the rev meter.
So looks like replacing the ECU is my only hope?
Shitty.
10-10-04, 10:59 AM
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As posted above... I have 4 gauge grounding wire to both the rear rotor, and all ECU ground wires have a direct negative battery connection, pressure sensor has a 12 gauge, and the alternator's ground points have all been cleaned (grinded).
I am starting to think its the secondaries now.
I went for a drive on the interstate (because when the hesitation starts, it always seems to be at a stoplight) so driving at 80+ for 20 minutes straight... well.. at 1:14 it started. However I could keep it right at 4K this time. 4th gear (had to downshift from 5th) dont wknow what my speed was... but if I kept the throttle below "30 percent" (going by AFC) then it would be fine... after that it was just like "oh no, dont think so"
I pull over. Shut off the car, take the terminal off for less than 3 seconds, and poof, back to normal. 1st gear pulls all the way to 7K.
And on the way back, it did it after 12 minutes... so looks like my time is getting very short.
I am starting to think its the secondaries now.
I went for a drive on the interstate (because when the hesitation starts, it always seems to be at a stoplight) so driving at 80+ for 20 minutes straight... well.. at 1:14 it started. However I could keep it right at 4K this time. 4th gear (had to downshift from 5th) dont wknow what my speed was... but if I kept the throttle below "30 percent" (going by AFC) then it would be fine... after that it was just like "oh no, dont think so"
I pull over. Shut off the car, take the terminal off for less than 3 seconds, and poof, back to normal. 1st gear pulls all the way to 7K.
And on the way back, it did it after 12 minutes... so looks like my time is getting very short.
Last edited by poor_red_neck; 10-10-04 at 11:07 AM.
10-10-04, 11:09 AM
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These grounds you added- was this to try to fix the problem, or did the problem start soon after the grounds were added?
Yeah, try an ECU...If that doesn't work, hopefully it won't take you three months to nail the bastard like it did on mine, lol...
Yeah, try an ECU...If that doesn't work, hopefully it won't take you three months to nail the bastard like it did on mine, lol...
10-10-04, 02:06 PM
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No, this was not a problem BEFORE the grounds... and the grounds have been there for about 3 weeks now, this JUST started to happen Friday.
10-10-04, 07:25 PM
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Well, just for ***** and giggles, I went w/o the TPS.
No hesitation
This is a TPS I bought from a member here too.... god dammit. Tested it AGAIN (tested it before, thought I had a clean sweep) but it goes from 1.0-1.4Kohm and never moves...
My question is why does it run fine with this faulty TPS, and all of a sudden poof.
Ah well. This is the problem though. I either drive with the TPS unplugged and refil my tank every 40 miles or so, or drive with the TPS and pull over every 15 minutes.
How would this work.... I un-do just the narrow range (the faulty one) and run with just the full range. Would this help out economy wise? This is JUST temporary until I can settle this with the guy I bought the TPS from and get a new one. I just can not afford the gas mileage Im getting with it unplugged.
Glad I dont have to replace the ECU though
No hesitation
This is a TPS I bought from a member here too.... god dammit. Tested it AGAIN (tested it before, thought I had a clean sweep) but it goes from 1.0-1.4Kohm and never moves...
My question is why does it run fine with this faulty TPS, and all of a sudden poof.
Ah well. This is the problem though. I either drive with the TPS unplugged and refil my tank every 40 miles or so, or drive with the TPS and pull over every 15 minutes.
How would this work.... I un-do just the narrow range (the faulty one) and run with just the full range. Would this help out economy wise? This is JUST temporary until I can settle this with the guy I bought the TPS from and get a new one. I just can not afford the gas mileage Im getting with it unplugged.
Glad I dont have to replace the ECU though
10-10-04, 08:00 PM
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no air pump or you just took off the hose to the air pump... if you dont disconect the air pump belt it will cause massive hessataion... just cut it off if need be...you cant plug the sob.. you have to disconect the hose... hope that helps
10-10-04, 09:37 PM
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That doesn't help at all.
The air pump has nothing to do with anything, my emissions are all removed. The only reason the air pump is there is because I dont have a dual alt pulley.... going with JUST the alt belt on the water pump can lead to slippage.... and not running the water pump at 100 percent.
Only reason the pump is venting to atmosphere is I haven't had time to get a piece of pipe to connect the silencer to the pump... until I get a pulley.
The air pump has nothing to do with anything, my emissions are all removed. The only reason the air pump is there is because I dont have a dual alt pulley.... going with JUST the alt belt on the water pump can lead to slippage.... and not running the water pump at 100 percent.
Only reason the pump is venting to atmosphere is I haven't had time to get a piece of pipe to connect the silencer to the pump... until I get a pulley.
10-11-04, 10:59 PM
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Well seems that the demon is back. Been driving w/o the TPS plugged in for over 24 hours now... and today it hesitated after 10 minutes of the car running.
SOB!!!!
Guess Im going back to replacing the ECU.
SOB!!!!
Guess Im going back to replacing the ECU.
10-12-04, 10:30 AM
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Just make sure you don't have anything getting hot and popping off/warping (like block-off plates) when she warms up, like mine did
For about 2 months I could have sworn mine was an electrical problem also...
Have you read anything out at the ECU while this is going on? The O2 sensor can actually give you a lot of info if you know how to decipher the numbers...
For about 2 months I could have sworn mine was an electrical problem also...
Have you read anything out at the ECU while this is going on? The O2 sensor can actually give you a lot of info if you know how to decipher the numbers...
10-12-04, 10:39 AM
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Dollars to Donuts your OMP is getting ready to take a ****.
What you are describing sounds like the ECU going into limp mode from a faulty OMP signal.... I had an 89 GTU that did the same thing, you'de reset the bitch and it would be good for a while and then blammo, but no codes. Finally, resetting it wouldn't help, and i DID get a code for the OMP. Replaced the OMP and its still did it.... Took the ECU apart and found a big black scorched area in the center of one of the boards where the OMP took the ECU with it when it went! Repaced the ECU.. No Problems.
try replacing the ECU and see if it still does it. This will eliminate the ECU. BUT KEEP THE OLD ONE incase the OMP goes and fries the new one!!!
What you are describing sounds like the ECU going into limp mode from a faulty OMP signal.... I had an 89 GTU that did the same thing, you'de reset the bitch and it would be good for a while and then blammo, but no codes. Finally, resetting it wouldn't help, and i DID get a code for the OMP. Replaced the OMP and its still did it.... Took the ECU apart and found a big black scorched area in the center of one of the boards where the OMP took the ECU with it when it went! Repaced the ECU.. No Problems.
try replacing the ECU and see if it still does it. This will eliminate the ECU. BUT KEEP THE OLD ONE incase the OMP goes and fries the new one!!!
10-12-04, 11:35 AM
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That's something that was HEAVILY on my mind, but forgot all about it.
I know its not secondaries... I think.. yesterday when it hesitated I could get it to about 6K with no detonation, but once I press the throttle just a bit more, stumble... again, not running lean/detonating.
I WAS getting a code for the position sensor before I basicly tore the engine to shortblock and removed emissions and replaced gaskets and fixed/checked all sensors.
I'm currently running 100:1 premix, and the OMP is still bolted to the car, however there are not oil lines... LIM and block is bolted shut, and there are bolts in the OMP.
I can't believe I forgot about the damn OMP problem. And like you said YOD, I get no codes.
Any news if the new Rtek 1.7 for S5 will disable OMP? That would be REALLY ******* sweet you know.
I took the MOP apart, cleaned inside the OMP where the position sensor reads... and checked ohm readings on the sensor... it checked out per the FSM... but I'm going with the OMP... DAMMIT I cant believe I forgot about the problem.
Is it even possible to get her to 6K in "limp mode?" It wasnt fast or anything.... and only in 1st or 2nd.
Sure glad I'm running premix hah.
I think I'm going to try and replace the OMP first, so I dont risk burning up an ECU.
The stepping motor is fine though, I NEVER got a code for the actual OMP.. so I dont think it'll fry the ECU right?
God damn this car man,
Such a love hate relationship
I know its not secondaries... I think.. yesterday when it hesitated I could get it to about 6K with no detonation, but once I press the throttle just a bit more, stumble... again, not running lean/detonating.
I WAS getting a code for the position sensor before I basicly tore the engine to shortblock and removed emissions and replaced gaskets and fixed/checked all sensors.
I'm currently running 100:1 premix, and the OMP is still bolted to the car, however there are not oil lines... LIM and block is bolted shut, and there are bolts in the OMP.
I can't believe I forgot about the damn OMP problem. And like you said YOD, I get no codes.
Any news if the new Rtek 1.7 for S5 will disable OMP? That would be REALLY ******* sweet you know.
I took the MOP apart, cleaned inside the OMP where the position sensor reads... and checked ohm readings on the sensor... it checked out per the FSM... but I'm going with the OMP... DAMMIT I cant believe I forgot about the problem.
Is it even possible to get her to 6K in "limp mode?" It wasnt fast or anything.... and only in 1st or 2nd.
Sure glad I'm running premix hah.
I think I'm going to try and replace the OMP first, so I dont risk burning up an ECU.
The stepping motor is fine though, I NEVER got a code for the actual OMP.. so I dont think it'll fry the ECU right?
God damn this car man,
Such a love hate relationship
10-12-04, 08:39 PM
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Another side effect to add to the list...
Was going down the road, when all of a sudden the tachometer went to 0. Car never changed... idle never changed or anything like that. Shut it off, immediately turned back on, back to normal. 10 minutes later (after I pulled over to reset ECU coz of ghey hesitation) it did it again. This time I just said **** it and put it in N and shut off the car, start, then put into 4th and kept on going (downhill).
I did this 3 times on the way home :-\
WTF!!!!! This **** is driving me crazy.
Was going down the road, when all of a sudden the tachometer went to 0. Car never changed... idle never changed or anything like that. Shut it off, immediately turned back on, back to normal. 10 minutes later (after I pulled over to reset ECU coz of ghey hesitation) it did it again. This time I just said **** it and put it in N and shut off the car, start, then put into 4th and kept on going (downhill).
I did this 3 times on the way home :-\
WTF!!!!! This **** is driving me crazy.
10-13-04, 10:52 PM
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bump... dont know why
Im going to check out the rpm signal wire. Its not the dash, as the AFC reads 0 as well. I think taking the plugs off the ECU so many times might have fucked something up. I didn't realise there was a little "door" to put tester leads on the terminals. Wish I knew that BEFORE all that trouble shooting.
Im going to check out the rpm signal wire. Its not the dash, as the AFC reads 0 as well. I think taking the plugs off the ECU so many times might have fucked something up. I didn't realise there was a little "door" to put tester leads on the terminals. Wish I knew that BEFORE all that trouble shooting.
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