Engine break ups when turbo kicks in. Any ideas?

[shadoof77]

Hey guys. New to the site but looking for a solution and ideas so throw some ideas out there. Just got my 99 gsx abot a month ago.
Okay basically through first gear the engine pulls hard and strong, as i shift up to 2nd and continue a pull once i hit about 4500 rpm's (about when the turbo kicks in) the engine seems to start breaking up as if the fuel/air ratio may be off because the engine still pulls through the gear, it just kinda dies out and seems like its not getting any power. It does the same through 3rd and 4th right about when the turbo kicks in. Not sure if its injectors or not but just looking for some solutions.
Thanks for your help

 

[BigBeans]

Is the car stock?

 

[shadoof77]

Car has some some mods done not exactly sure what spec on the mods done but i know turbo was swapped, intercooler, piping, exhaust, intake. but as for the engine its stock but it was rebuilt. I do also know that the turbo is tuned to stock settings still, 8g

 

[GRAVEDIGGER]

Has there been a basic tuneup done recently? (plugs, wires, fuel filter) If not or you don't know when the last time it was done I would start there first.

 

[shadoof77]

yea, did all the first day i got the car. including belts, and battery (thinking it may have been not getting enough electrical power) and took it to a autoparts store and tested the alternator and it checks out fine.

 

[GRAVEDIGGER]

Have you done a boost leak test? You might want to try that next to make sure you don't have any leaks anywhere.

 

[shadoof77]

yea tried that already no leaks though... its got me stumped... not sure if i should just go get bigger injector, fuel rail, fuel pump, etc...

 

[GRAVEDIGGER]

Too bad you don't have your profile filled out. It's hard to point you in the right direction without knowing what mods are done to your car.

 

[shadoof77]

I know, but it was a month ago when i bought the car, i understand the concept of engines, turbo's, the basic functions and how it works but when it comes to name brand stuff like greddy, hks i dont know to many of them nor their specs of their products and such and such. So, when i went and got the car, the guy told me what was done but i really didn't catch the name brands or specs nor was i giving reciepts for the mods. So, unfortunately i cant help out with the the specs of stuff or mods on the car until i go purchasing new mods. but i greatly appriciate your help and input

 

[GRAVEDIGGER]

I know what cha mean. It's just hard to say what you need to do without knowing exactly what has been installed on the car. You say the turbo was swapped, but it is tuned to the stock settings. That doesn't make much sense to me. So it's hard to say what turbo you have on it or if the injectors have been changed etc. Sorry I can't be of any more help.

 

[BigBeans]

what did you gap the plugs to?

 

[shadoof77]

yea, i just dont wanna blow $500 on injectors and fuel system stuff just to have the same problem occur. Not saying that one day i wouldnt eventually buy that stuff, I just rather put the money torwards getting the car fixed ya know.

what did you gap the plugs to?

i bought them from mitsubishi pre gap, but they are .032

 

[BigBeans]

yea, i just dont wanna blow $500 on injectors and fuel system stuff just to have the same problem occur. Not saying that one day i wouldnt eventually buy that stuff, I just rather put the money torwards getting the car fixed ya know.



i bought them from mitsubishi pre gap, but they are .032

Regap them to .24 and go for a drive. Let me know if that fixes it. If the coils are a little weak you could be getting spark blowout.

 

[shadoof77]

what did you gap the plugs to?

Regap them to .24 and go for a drive. Let me know if that fixes it. If the coils are a little weak you could be getting spark blowout.

Alright I'll give it a go

 

[rarson]

I usually gap mine to about .025" or so, but you can never trust pre-gapped plugs. I've seen them come as high as .040". Most of the time they're not even consistent across the set. Regardless, I believe the spec is .028" and that's as high as I would go. I know my car tends to break up if the gap is set any higher.

Also, I've found that NGK coppers work the best. Iridium plugs are a waste of money. They also seem to get blown out easier than the coppers.

 

[jrohner]

.032 plug gap is probably the issue, put them at .026 or so, less if your running high boost.

 

[shadoof77]

yea im going to pull the plugs out tomorrow regap them at .025, and/or maybe pick up the coppers NGK.

 

[BigBeans]

yea im going to pull the plugs out tomorrow regap them at .025, and/or maybe pick up the coppers NGK.

NGK BR7ES or, if you want longer life but less resistance to detonation, BPR7ES.

 

[warranty]

The first thing I'd check is your spark plug wires.

Try this: rev all the way to redline but use only part throttle (not full throttle) so you don't build boost in 2nd or 3rd gear (do it in a safe place, obviously) and if you don't get the stuttering, then your problem is most likely (1) the plugs, (2) the plug wires, or (3) the ignition coil, in that order. If you have a friend with a DSM, borrow his spark plug wires for a quick check.

If your ignition system is unhealthy, it's possible you don't get the problem in 1st gear because the engine load is simply not high enough in the low gear.

Warren

Okay basically through first gear the engine pulls hard and strong, as i shift up to 2nd and continue a pull once i hit about 4500 rpm's (about when the turbo kicks in) the engine seems to start breaking up as if the fuel/air ratio may be off because the engine still pulls through the gear, it just kinda dies out and seems like its not getting any power. It does the same through 3rd and 4th right about when the turbo kicks in. Not sure if its injectors or not but just looking for some solutions.
Thanks for your help

 

[BigBeans]

Warren, i know you had the best intentions, but try skimming the thread before posting.

OP said he just did a full tune up. (post #5)

 

[ricktb]

I had a similar issue with my spark plug gaps.. seems like the engine would skip or miss rapidly, and a loss of power. Found the plugs were worn with gaps between .040 and .080.. replaced them with gaps of about .028 inches and it pulls strong to redline. gotta be that or an ignition issue, or an air/fuel issue.

ps I am running the ngk iridium plugs with slightly higher than stock boost (15psi) and find them to be great.. tho I've heard if I want to go higher boost I may need a cooler plug

 

[warranty]

Understood...I did read that he did a "tune up", but since it's such a generic term I just wanted to make doubly sure he can do an easy check.

In the old days tune-up means checking/adjusting distributor point, changing spark plug, adjusting valve lash, checking the carburetor, etc. These days on modern electronic fuel injected cars, a "tune up" wouldn't consist of much more than a spark plug change would it?

Warren, i know you had the best intentions, but try skimming the thread before posting.

OP said he just did a full tune up. (post #5)

 

[Long Duk Dong]

Sounds like it may be blowing the spark out when the turbo starts really pushing some air.

 

[wakehype7]

i've been fighting issues with my DSM, i've had the same kind of issue with mine a few times, it'd pull hard up till around 4K rpms then it'd just lose power and cut in and out around 4k. i found it to be my CAS, it ended up that the wiring was frayed so i rewired it and put in a different sensor. hope this helps!

 

[BigBeans]

Sounds like it may be blowing the spark out when the turbo starts really pushing some air.

You're a valuable contributor to the forum, aren't you?

If you're going to post, post something worth saying. Enough with the "hmmmmm" and restating what has been said a dozen times to get your post count up BS.