6k rpm breaking up

[Hydecotsi]

Ok so I just bought my 90 plymouth laser fwd turbo..it's got exhaust on it and the filter cover was removed and a k&n filter installed.....that's how it was when I bought it...so my problem is it pulls great fells good and it hts 6k rims and breaks up bad. I pulled the plug the where kinda kite ( detonation) installed new ngk plus bre7es I think and gapped them to .028 make a pull and no change the guy I bought it's from said it was running 14-15psi but by the gauge it at the factory. 9-10psi any help would be greatly appreciated I flushed the radiator and changed the oil inspected the timing belt all is good its in timing also

 

[c2ypt1c]

Could be the plug wires. NGK's are pretty much the gold standard.
I've had wires go bad causing misfires/break up in the past.

Check the coil pack resistance:
http://www.dsmtuners.com/forums/new...suring-coil-pack-correctly.html#post152928590

or the power transistor (ignition control module):
http://www.dsmtuners.com/forums/articles-electrical-wiring/229419-how-test-power-transistors.html

as stated in the article, you can use a blow dryer to heat up the power transistor and see if you can induce a misfire.

 

[Hydecotsi]

Could be the plug wires. NGK's are pretty much the gold standard.
I've had wires go bad causing misfires/break up in the past.

Check the coil pack resistance:
http://www.dsmtuners.com/forums/new...suring-coil-pack-correctly.html#post152928590

or the power transistor (ignition control module):
http://www.dsmtuners.com/forums/articles-electrical-wiring/229419-how-test-power-transistors.html

as stated in the article, you can use a blow dryer to heat up the power transistor and see if you can induce a misfire.

Okay will try this first thing tomorrow and ill post what I found out

 

[4G Power]

Ok so I just bought my 90 plymouth laser fwd turbo..it's got exhaust on it and the filter cover was removed and a k&n filter installed.....that's how it was when I bought it...so my problem is it pulls great fells good and it hts 6k rims and breaks up bad. I pulled the plug the where kinda kite ( detonation) installed new ngk plus bre7es I think and gapped them to .028 make a pull and no change the guy I bought it's from said it was running 14-15psi but by the gauge it at the factory. 9-10psi any help would be greatly appreciated I flushed the radiator and changed the oil inspected the timing belt all is good its in timing also

Do not go by the factory boost gauge, it is in no way accurate to how much you're boosting.

 

[bigbird94]

Maybe try re gapping the plugs, from what ive found each car/setup/fuel likes a different gap.

 

[NHerron]

This is a free site with free help. It's very possible a knowledgeable member could swing by a thread and solve problems not even a dealer could figure. The least a person could do when starting a thread is explain their concerns and problems in the most coherent way possible. That means inserting a period every once and a while, spelling, etc. Basically -ditch the 'don't give a shit' text style when on tuners and you'll have much better results.

You should be running BPR6ES plugs. Start from there.
http://www.dsmtuners.com/forums/frequently-answered-dsm-questions/233421-spark-plug-faq.html

 

[c2ypt1c]

This is a free site with free help. It's very possible a knowledgeable member could swing by a thread and solve problems not even a dealer could figure. The least a person could do when starting a thread is explain their concerns and problems in the most coherent way possible. That means inserting a period every once and a while, spelling, etc. Basically -ditch the 'don't give a shit' text style when on tuners and you'll have much better results.

A little harsh, don't you think? (8th post...cut him some slack? and I doubt he has a "don't give a shit" attitude)

You should be running BPR6ES plugs. Start from there.
http://www.dsmtuners.com/forums/frequently-answered-dsm-questions/233421-spark-plug-faq.html

The difference between BPR6's and 7's is minimal, I've ran 7's on a t25 for years without issue.

I suspect either the wires or a boost leak.

 

[NHerron]

The difference between BPR6's and 7's is minimal, I've ran 7's on a t25 for years without issue.

I suspect either the wires or a boost leak.

So now we all know 7's can be used because you ran them 'without issue'. Right on.

Anyway. There are no 'bre7es' plugs. Either you didn't notice that or are assuming best case scenario, which would be a fatal mistake.

I 'bi***' at OP's like this because in the real world people like to assume things and forget the obvious. Before you know it someone's whippin out the techy diag. test equipment when it's a corroded terminal.
Giving strangers benefit of the doubt and wasting everyone's time? Not my style.

 

[c2ypt1c]

So now we all know 7's can be used because you ran them 'without issue'. Right on.

They can be used, especially if you run the car hard (t25 blowing hot air). 7's dissipate more heat (relative to 6's) and is therefore a "colder" plug. Too cold a plug can cause unburnt conductive deposits to accumulate on the insulator, which does not happen immediately, but over time.

Considering he swapped in brand new 7's and still had the issue, it points to something other than fouled plugs. I'd consider plug gap before heat range.

Anyway. There are no 'bre7es' plugs. Either you didn't notice that or are assuming best case scenario, which would be a fatal mistake.

Fatal? That's a bit dramatic. It's pretty obvious what he meant.

I 'bi***' at OP's like this because in the real world people like to assume things and forget the obvious. Before you know it someone's whippin out the techy diag. test equipment when it's a corroded terminal.
Giving strangers benefit of the doubt and wasting everyone's time? Not my style.

Fair enough, but you could tone it down a notch. I hardly consider multimeters or blow dryers "techy" diagnostic equipment, if that's what you're implying. The above mentioned tests take all of five minutes...Like you said, this is a free site. If you feel like you're wasting your time, there's the door.

 

[AK Maniak]

I was having very similar issues the other day and it turned out to be the power transistor. Let us know what you find.

 

[cyhm]

Start simple. Do a boost leak test. It doesn't matter how much boost your gauge is reading because you still don't know how much is leaking. I had a terrible break up at 6k and was still hitting target boost or atleast close to it. Guess what. It was a boost leak.

 

[NHerron]

You're very indecisive, you know that? How many edits does it take?

Look, you're not getting it. Heat range, I did this I did that, breaking down plug basics, whatever. The OP typed a plug that doesn't exist. I'm not even guessing the problem at this point.

You wanna continue pissing up a tree, PM me. Otherwise lets see if Mr. Spellcheck is coming back and resume trying to help him.

 

[jakelandry]

Also try pulling the valve cover and ensuring all your rockers are where they belong. Old valve springs/ bent vaves tend to allow them to pop off reducing the volume of air going into that cylinder. Feels just like hardcore spark blowout about 6k and up.

 

[Hydecotsi]

Sorry guys. I've been busy working on my other car my 1g eclipse. Come to find out the fuel filter was plugged up. I'm sorry if I offend anyone. I don't have a I don't care attitude. Ik a good amount about cars but not these dsms. I have been around Hondas most of my time and their very similar other than the whole head gaskets and timing belt problems. I am no have boost cut and the factory boost selonid is still plugged it I tried another unit ik that worked. Their was no different. I've done a boost leak test and fixed them all except the leaky tab seals it a very small leak. Y is this thing boost cutting?

You're very indecisive, you know that? How many edits does it take?

Look, you're not getting it. Heat range, I did this I did that, breaking down plug basics, whatever. The OP typed a plug that doesn't exist. I'm not even guessing the problem at this point.

You wanna continue pissing up a tree, PM me. Otherwise lets see if Mr. Spellcheck is coming back and resume trying to help him.

I'm so sorry I mean a bpr7es sorry mister. No need to be an a** about it.

 

[codeofdastreets]

have a similar issue with my 2g but have changed coil packs, cas, transister, plugs, wires, injectors, alternator, diffrent aem, resistor box, diffrent maps, tested gas, boost leak test ... all seem to be no help... compressiom test and leak down test are good?? I have gapped plugs down to .017, tryed ignition box, have dont plenty of olm test from ecu connectors to sensor pins, have checked timing, have inspected valve train, logged fuel pressure.. the car seems to missfire under load like 4-5 psi if i ease into it it wont missfire.. any ideas???