Car will not rev past 7k..no matter what i try

[turboglenn]

I"ve never had this issue before, but i've put in cams, alcohol, gapped my plugs down to .025. and added the J&s knock sensor... i've tried it with all extra off and on and it will not go past 7220.. it will sound like rev limiter at first, then the car just shuts down untill you let of and shift.

WTF?????

anyone got any advice? I've NEVER EVER had this issue with my car, and not much has changed, the timing is dead on..what gives?

 

[turboglenn]

Also, this has to be ignition related, as the stand alone shows no malfunctions, and the duty cycle and AFR are constant all the way through teh rev range, even past where i set my limiter.

Could this be the plug gap? or would it more likely be something in the transistor or coils? I have spares of each at my shop, i just hate working on it in this cold ass weather

 

[ajinvista]

Also, this has to be ignition related, as the stand alone shows no malfunctions, and the duty cycle and AFR are constant all the way through teh rev range, even past where i set my limiter.

Could this be the plug gap? or would it more likely be something in the transistor or coils? I have spares of each at my shop, i just hate working on it in this cold ass weather

Why don't you call me, my garage can be heated and there's only one other car in there, the Talon is done. I may need some tuning help. I was getting some knock up over 5k. I also know these 2 guys that may be able to help. Call me this week. How's the job? And the tranny?

 

[turboglenn]

Why don't you call me, my garage can be heated and there's only one other car in there, the Talon is done. I may need some tuning help. I was getting some knock up over 5k. I also know these 2 guys that may be able to help. Call me this week. How's the job? And the tranny?

The job is brutal, the tranny is awesome, i hated teh first 400 miles on it and still have trouble with low speed shifts. but Jon @ TRE said that he built teh preloads and whatever in my trans to shift it's best between 5 and 9k and can be pushed to 11k..I"llnever turn over 8, but i need to get this shit figured out. I may grab some coil packs, extra ignitors/transistors and swing over.

You got a goos stock of tool or shoul i being a few of my own as well?

Send me a PM with your contact info in there. I've changed phones and am workingon rebuilding my contacts list.

My works schedual is hell but i'd be glad to help you get your car tunes out. Bad thign is i don't have any logging stuff for a 1g. I can pull teh wideband from my car thoughand we can get yours tunes if you don't have a wideband.

Hell, let me know.maybe we can get a few cars on track in one day (highly unlikely when speaking DSM, but we can try )

 

[ajinvista]

I have a good amount of tools, mostly anything needed for a 1G. But if you think of anything bring it. Let me know I'll move some junk and heat it up.
BTW, car seems to run pretty good, keeping the boost around 10-12psi and hanging under about 4500rpm. But you know how it is I just had to hit once, got about 80 miles on the motor. Went on a little sunday drive today down 80 and back thru gretna to Omaha. There was some dork and his wife in a Hemi 300 kinda sneering. Funny thing is I have the real Hemi! He knows that now. I can't wait to really get into this thing.
Later, call me this week dude!

 

[turboglenn]

Send me your contact info in a PM, i dint' have the email setup on my laptop, to send you mails. Anyway, send me the info and I'll call you this week. How many miles on the motor so far? you should vary the RPM up and down keep changing gears as much as possible, give it some higher RPM (not redline areas though) and don't do too much highway driving, make sure to get in the boost some to help the rings sea against' the cylinders

 

[turboglenn]

BTW, still looking for any insight if anyone's had this issue before and solved it. I'm on a haltech ECU so it will tell me if it's at fault, but it can't tell my if the ignition components are bad.

I've st coil charge times anywhere from 2.5ms to 5ms and nothing changes, the triggers are consistent and i run a black top CAS, and have a spare black and green (long wire style) if need be

 

[turboglenn]

DAMN IT!!!! As soon as i cleaned, re-wired and relocated all my power and ground cables to see if i maybe had a bad hookup from the tranny install. It starts SNOWING ARGHHHHHHHHHHHHHH...EVERY TIME i get a part or try and test something we get at least a few inches of snow. It's like god is saying "Just park the damn thing, it's a DSM you know" :


EDIT/UPDATE:
well, i said o hell and went out to let her spin up in teh wet streets anyway. THe first pass i thought i was good, all the way to 7800 with no issues, then with every pull it got worse and worse to where it was shutting down again. Next is a transistor since coils normally just fail or crack. Seems like something is starting to get hot and then starting to shut down and i've seen motorcycle coils do that and they're really not much different, and they usually shut down untill they cool off.

Scratch bad grounds or poor power connections in this case. Usually that's the first sign, but at much lower levels than what i'm experirncing. And i fixed all those today!

 

[turboglenn]

OKay, i just crawled under my car to get to where i hid my transistor and replaced it, replaced the coils and still... nothing, it's still breaking up in high RPM's but does not seem to be shutting down completely this time(but i didn't push it as hard either). It seems the best improvement so far has been the ground wire cleanings, maybe i need to add more? I didn't see any cross arcing in the wires at night, so i'm ruling them out for now.

Anyone got any last thougts? The only things left are the CAS (black top), plugs (plugs are new BPR7ES's gapped to .025), wires ( 6 year old magnecores) or signal interference to the ECU from the CAS, but it shows a steady signal.

Now except for adding more grounds i'm lost. Does anyone know if the transistor is supposed to be linked to the coils as far as grounding is concerned? The coils are in the manifold and the ignitor is on the firewall now.

please ANY ideas i'll try em...

 

[Black_Bullet]

OKay, i just crawled under my car to get to where i hid my transistor and replaced it, replaced the coils and still... nothing, it's still breaking up in high RPM's but does not seem to be shutting down completely this time(but i didn't push it as hard either). It seems the best improvement so far has been the ground wire cleanings, maybe i need to add more? I didn't see any cross arcing in the wires at night, so i'm ruling them out for now.

Anyone got any last thougts? The only things left are the CAS (black top), plugs (plugs are new BPR7ES's gapped to .025), wires ( 6 year old magnecores) or signal interference to the ECU from the CAS, but it shows a steady signal.

Now except for adding more grounds i'm lost. Does anyone know if the transistor is supposed to be linked to the coils as far as grounding is concerned? The coils are in the manifold and the ignitor is on the firewall now.

please ANY ideas i'll try em...

i had a similar problem and then i changed the wires for some stock spark plug wires and problem fixed, and i guess it turned out that i was missing up top because the wires began arching too bad from being old...
You may want to check out your ecu board, and ecu harness connections also, and sorting thru everything thats ign related. Then take a close look at whatever your tuning with.

Does it break up worse in a higher gear vs a lower gear? That def would sound like thats ign related, i think that the load on the electrical current goes up rapidly as you go into a higher gear due to more load on the engine...
And just for the hell of it do a boost leak test.

Also i just had some success with running the non projected style spark plugs..
You just listed you had the project style ngks, the BR7ES work much better in not giving you detonation than the BRP7ES... It was talked about in my "High boost e316g" thread in these tuning forums. I know you run meth , but ay everything helps.

 

[turboglenn]

i had a similar problem and then i changed the wires for some stock spark plug wires and problem fixed, and i guess it turned out that i was missing up top because the wires began arching too bad from being old...
You may want to check out your ecu board, and ecu harness connections also, and sorting thru everything thats ign related. Then take a close look at whatever your tuning with.

Does it break up worse in a higher gear vs a lower gear? That def would sound like thats ign related, i think that the load on the electrical current goes up rapidly as you go into a higher gear due to more load on the engine...
And just for the hell of it do a boost leak test.

Also i just had some success with running the non projected style spark plugs..
You just listed you had the project style ngks, the BR7ES work much better in not giving you detonation than the BRP7ES... It was talked about in my "High boost e316g" thread in these tuning forums. I know you run meth , but ay everything helps.

The ECU is fine, that was the first check, then the wiring, then replaced everything in the ignition except the wires and CAS. I'm going to try wires next.

I'll double check my ECU to chassis ground to be sure there as well. but the signal and it's grounds are all okay in the ECU, it's a full stand alone so that's what i tune and log with. it's a very nice system. This is not in teh ECU, but somewhere in between it and the spark plugs

It happens at RPM's of 7220 and above, it starts breaking up real bad and then the more you push it the harder it shuts down. it doesn't matter if i'm at 25psi or 13psi, it's exactly the same RPM and degree of break up.

I'm also going to run a few more grounds from teh battery to firewall and from the transistor to coil packs next. What the hell, i've got spools of wire laying here, just need to buy some bigger loop connectors.

 

[Black_Bullet]

The ECU is fine, that was the first check, then the wiring, then replaced everything in the ignition except the wires and CAS. I'm going to try wires next.

I'll double check my ECU to chassis ground to be sure there as well. but the signal and it's grounds are all okay in the ECU, it's a full stand alone so that's what i tune and log with. it's a very nice system. This is not in teh ECU, but somewhere in between it and the spark plugs

It happens at RPM's of 7220 and above, it starts breaking up real bad and then the more you push it the harder it shuts down. it doesn't matter if i'm at 25psi or 13psi, it's exactly the same RPM and degree of break up.

I'm also going to run a few more grounds from teh battery to firewall and from the transistor to coil packs next. What the hell, i've got spools of wire laying here, just need to buy some bigger loop connectors.

Definitly a strange problem for it to be consistently at the same rpms.
If it was a ground or bad wire it likely could be within the area of rpm but not exactly the same. Im starting to think its an internal problem ecu or tune related. Something in your full stand alone settings is skewed maybe.

 

[turboglenn]

I've quadruple checked everything down to the solder joints on the shielded wires from the CAS to the ECU... The AFR's and Timing are dialed in all teh way to 10,500RPM so if i could rev that high, the setting would be close enough to run. I have gained some RPM with the extra/cleaned grounds and power wires.. Still got to run a few more of those, i want to loop one from the transistor to coil pack, to battery, firewall and then to ECU's common chassis ground... And new iwres still need to get ordered. I'm going to figure this out or send the E6k in for service, but it's never flinched a beat in 9 years.

I"m thinking if it's not the wires (which should have been replaced first anyway) that it may be the CAS's signal breaking up. But i'm not anticipating that to be it. I know it's going to boil down to the smallest dumb little thing (most likely DSM specific j/k) And i'll get it worked out by summer, the alst resort is an ignition amplifier box. But i usually shift at 6900 anyway, so this isn't hurting my really bad, just a big bothersome wiring issue. I can still hold 25psi with hardly a trace of knock on pump + meth so i'm psyched about that, even with a rough tune because i've been chasing this issue instead of perfecting AFR's up to there

 

[rrussell]

This may sound way stupid but I'll throw it out there anyway because it got me last year.

I had the same problem, wouldn't rev pass x rpm and chased down everything i could think of.(plugs, spark plug wires, added four grounds, check fuel pressure, had the injectors flowed, boost leak tested, different fuels etc.)

One day I'm driven down the road and noticed that my batt volts were under 11.5. Usually they were at 12.5+

So I started looking around and finally noticed that when the last time I change oil i must of bump the alternator main lead and loosing it. The thing wasn't' really loose bit loose enough. Put about a half turn on it and check the voltage. Back to normal took it out for a test and I really still didn't believe that would of been causing the reving problem. But it was.

One other thing it could be is a injector that is not flowing at higher rpm. I just fixed a customers car that had one injector that was clogged. Was only flowing 60%

 

[turboglenn]

The alt. wire is a good thought, I wasn't even paying attention to voltage. I am90% sure the injectors are fine. I keep up regular on filter replacements and had teh injectors flowed about 2 years ago, but with todays gas who knows *shrugs*...

Another postal employee off to work in 17* weather..... Be back tonight still pondering and wondering on this one

 

[44pirate]

I had a similar issue. I would be able to rev it out to redline maybe once and then it break up just cruising at around 3000rpm. Changed everything just like you did. Seemed once it got warm it would have same issue. I too HAD a black top CAS. Replaced it with a silver top CAS and no more issues.

 

[Black_Bullet]

The alt. wire is a good thought, I wasn't even paying attention to voltage. I am90% sure the injectors are fine. I keep up regular on filter replacements and had teh injectors flowed about 2 years ago, but with todays gas who knows *shrugs*...

Another postal employee off to work in 17* weather..... Be back tonight still pondering and wondering on this one

Im thinking that if it was a fuel problem, wouldnt you just lean out were the clogging started to restrict the flow. Therefore you'd detect knock or something if it was fuel related.

This may sound way stupid but I'll throw it out there anyway because it got me last year.

I had the same problem, wouldn't rev pass x rpm and chased down everything i could think of.(plugs, spark plug wires, added four grounds, check fuel pressure, had the injectors flowed, boost leak tested, different fuels etc.)

One day I'm driven down the road and noticed that my batt volts were under 11.5. Usually they were at 12.5+

So I started looking around and finally noticed that when the last time I change oil i must of bump the alternator main lead and loosing it. The thing wasn't' really loose bit loose enough. Put about a half turn on it and check the voltage. Back to normal took it out for a test and I really still didn't believe that would of been causing the reving problem. But it was.

One other thing it could be is a injector that is not flowing at higher rpm. I just fixed a customers car that had one injector that was clogged. Was only flowing 60%

This could be likely. Get a volt gauge on it.
Replace your cas while your at it if you have a 6bolt motor, but since your a 2g I dont think your CAS is the same as the 1gs. if you do have it though, i believe the best CAS to use is the 93-94 CAS which IS the black top one. The pre 93 CAS used a optic sensor i believe while the black top used a hall effect sensor or something which is suppose to have higher resolution. http://www.dsmtuners.com/forums/newbie-forum/215140-hall-effect-cas.html

I had got a black top one for mines a year ago.

Besides all that, i still stay get new wires. If all else fails just dump some money for a C.O.P ign.

 

[turboglenn]

Well, the battery volts are fine. 13.5 -14.1 on average, and it's not going lean it's going way rich from teh spark not firing and it just shooting gas out the exhaust valves.

I have a 6 bolt motor in the car , so i think i'll try my spare CAS ( one of the 2 spares i have) and see if that helps after i try wires.

There's no knock or anything though, so the tune is good enough, a tad rich, but "safe" for repeated testing of 7500+ pulls

I MIGHT go COP, but I want the problem solved before trying to "band aid" the situation with a completely different ignition.

 

[turboglenn]

damnit!! Just when i thought i had it sorted out i ran the motor up and it did it AGAIN!! At this point i've tried everything i can think of besides running fresh wires from teh ECU to the ignitor/power transistor. But i doubt it's going to be faulty trigger wires.

Anyone got any oddball or unmntioned advice on this

I've changed
Coils
transistor
cleaned and added grounds
Cleaned all power wires
Checked all solder joints from the aftermarket ECU to the corresponding ignition part.;

I've never seen a CAS start acting up, they usually just stop working, but i'm about to change it here soon just to eliminate that as well

ANY ADVICE?????????????????? I'm pulling my fricken hair out

 

[TurboAnything]

If your cas was bad then your rpm signal would not be steady. Have you changed the wires? I would do that first before anything.

 

[turboglenn]

If your cas was bad then your rpm signal would not be steady. Have you changed the wires? I would do that first before anything.

YOu know what, my CAS does fluctuate about 3 degrees ( it will go a degree or two either side of the baseline setting even when the timing is locked and teh CAS is tight) but i let that go thinking it was fluctuation in the timing belt setup since i replaced everything on it when i put the cams and stuff in a month ago

I haven't changed wires yet, work's been kicking my ass sso i've just used it to go point A to B and back home.

I want to order more magnecores, but without having any wires to test with and see if that's it i don't want to spend any extra ( the TRE tranny i had to buy set me back BAD) but was well worth it.

I think i'll ask drdouglas (a member here) if i can try his wires for a pull or 3 and see how that feels.

I can't find anything wrong with the wires when testing impedence or enything like that. I've even held my hand on each one at a time and revved the motor while tracing the whole route of the wire looking to get a shock from a crack in the insulation, but they seem fine *(*&$&#*^%^)(*^^$$!!!!!!!!!!!!!!! <-----how frustrated i am


EDIT: actually i think you're onto something. I just pulled some logs. My RPM signal under WOT does seem to fluctuate back down a few RPM(maybe 30-50RPM) before going up to the next higher RPM. (example is that it will read 4800, 4820, 4825, 4800, then back up to 4950 and it repeats. THe only way i can tell though is to log the RPM signal at 180 frames per second and then study through it, but sure enough i saw an unsteady signal

 

[talontd92tsi]

I have heard of a CAS causing exactly what you are talking about, but not to the extreme you are. If you have a spare, its free, swap it out and see what happens. If nothing changes, you can add another one to your list and go from there.

 

[turboglenn]

Put a new CAS in today and reset timing, no luck

Damn, this is really starting to erk me!!!!! The only thing i haven't done now is replace the plug wires , but they tested out okay on resistance, and I haven't been able to see any arcing when looking at them in the dark and revving the car. Plus it happens dependant on RPM not load or boost.

The only thing left is to rewire the entire ignition system. Something i'm not looking forward to, but hey, if it'll fix this issue, i'll do it. But if i do, Im running the fine shielded wire all the way to and inside of the CAS and going direct from the ECU to the ignitor instead of through the stock harness.

If it still does it my only thing left is to try is another ECU, not a very good option at $1400.00+ for just an ECU. Not to mention that my model is 10 years old so i would have to upgrade. But this ECU has passed all tests as far as being in working order, but who knows, somehting could be going wrong insisde the ECU at 7200 RPM i guess *shrugs*

 

[MIdsm]

The plug wires may arc through the side of the spark plug boot right to the head and may look and test OK. I was in a situation to pull the wire (Magnecore) off the plug with the car running, look down the plug hole and see arc going sideways right through the plug boot. Before the wire was pulled off the spark plug no arcing was visible.

Back in October of '03 in the Cars & Car Conversions magazine Dave Walker wrote about tuning a car on his dyno and having a terrible misfire above 7000 rpm. Mr. Walker tested the following without finding a problem - wiring, plug wires, coil energy output, injector setup, fuelling and ecu was bench tested. Following the troubleshooting and elimination of all the obvious causes of misfire Mr. Walker thought that problem may be caused by weakened valve springs as he had a previous experience where weakened valve springs caused a misfire that slowly went lower in the rev range as the springs gave up the ghost. Mr. Walker manufactures Emerald brand ECUs, has a shop with a dynamometer where he works on a variety of cars and also writes Walker's World, previously for above mentioned CCC and now for Practical Performance Car.

Good luck.

 

[turboglenn]

MIdsm, thanks for the input! I guess next i'll just order a new set of wires, these have served well for many years. I do have to note that this showed up after installation of new and bigger cams, so this could be because i'm on stock valve springs, but i've never heard it be so severe before. At least not to the extent mine is mis-firing to. But that doesn't mean that it's not my issue. I will get wires next and when money allows, i'll throw in some springs too. If nothing else, it's agood reason to go stroker where i wouldn't have to rev high anyway : (that was a joke, i wouldn't build the motor anymore before sorting out my current issues)

The one good thing is that right now the missing is above my daily operating RPM enough that i can still run the car good and hard without having to put up with this. It's only when i try to squeek them last few RPM out that it happens and i only have to do that in really close runs, but most of the time i'm so far ahead before i get to that RPM that it's not even funny.