odd problem after rebuild

[Lil' Shaun]

I now have 300 miles on the engine i just rebuilt. after about 250 miles is started kinda acting up, but seems to mainly do it when pulling out of the parking lot at work. it starts and runs fine in the lot but when i go to pull out onto the street it acts like i'm just rolling out into traffic. I'll give it about half throttle, it won't rev or pick up speed, but it does build boost as it slowly rolls across two lanes of traffic. then it just takes off like a bat out of hell. some times when i'm driving it feels like it does it a little just before the turbo spools, and it never makes any unusual sounds wile doing this.

if it was a boost leak wouldn't it do this every time the turbo spools and not just once or twice a day

 

[TsiJohn333]

any codes? and either way i would definitely do a boost leak test. start small check for boost leaks, check your spark plug, spark plug gaps, timing...etc. and does it hesitate under boost or does it do it in vacuum or both?

 

[drewboi]

mine did that when i was getting knock

 

[luv2rallye]

Could easily be a vacuum leak that gets overwhelmed when the turbo kicks in. Check your hoses and hose connections.

 

[Lil' Shaun]

no codes, if i dont let off the gas it doesn't stop till it gets full boost. I have an afc hooked up and its not showing any knock.

 

[TsiJohn333]

do a boost leak test. make sure all your couplings for your intercooler are on good and tight as well. we should do a blt on a regular basis. did you check your tps? i had this problem on my 98 gst sypder and it didnt throw a code right away.

 

[delta448]

Check AFC wiring splices, make sure there's no shorting out.
Stock injectors? Settings? Profile is not up to date.

 

[Lil' Shaun]

stock injectors and settings are zerod out

 

[92AWDHX40]

do a boost leak test, they really help invested in a compressor years ago, and a blt takes about 10 minutes, and cost only a few bucks!

 

[Lil' Shaun]

ok so the problem got a lot worse today. now it feels like its running out of gas.
it doesn't matter if the engine is warm or cold.
it always does it for the couple minutes after starting the car.
it sounds like its missing when its doing it.
if I let ti run for about 5 minutse it runs fine.
runs like crap under vac and over 8 psi of boost.
it runs fine from 0-7 psi or after running a wile from idle to 7psi.
found a small boost leak at the throttlebody shaft.
the problem got way worse after changing the plugs.

I'm starting to think it might be the fuel pump.
today was so bad I had to park it and borrow my moms lancer.

 

[_MACE_]

Do you still hear a real strong whine from the fuel pump when priming?

 

[Lil' Shaun]

i have never been able to hear the fuel pump.
I found the boost broblem i had a split coil boot.
but it still bogs the first couple minutes, but only in gear and only after going around a left turn

 

[luv2rallye]

but it still bogs the first couple minutes, but only in gear and only after going around a left turn

Does it do it with a full tank? Around a corner a low tank may move gas away from the pickup tube.

 

[tazndrew04]

sounds like something to do with fuel,if you dont hear it whine when u turn the key to the on position without starting it you should hear that famous whine,if not than id say ## fuel pump

 

[BLINKY619]

sounds like something to do with fuel,if you dont hear it whine when u turn the key to the on position without starting it you should hear that famous whine,if not than id say ## fuel pump

mine doesnt wine.. i dont know if a rewire is to blame...

 

[luv2rallye]

On all dsm 1g's and only 2g turbos the fuel pump only has power applied when the engine is turning (CAS pulses) and key on.

 

[Lil' Shaun]

well, its not the fuel pump. I put the 255 from my talon in the eclipse and it still does it.
it goes form sounding like a car to sounding like a subi.

I'm starting to hate this car.

 

[_MACE_]

On all dsm 1g's and only 2g turbos the fuel pump only has power applied when the engine is turning (CAS pulses) and key on.

This is some technical shit you dont learn that often. No fuel pump prime on turbo models.
good to know. The car acted up worse after plug change...Thats weird as hell makes me think the wires are on wrong. Thats a hard one man. Google is your friend, dont light the car on fire yet. water in the gas? Sloshing around mixes the gas with water and will create a bog. (learned this from working on jetskis)

 

[Lil' Shaun]

I got it back to the first problem it ran worse after a plug change because one of the boots on a coil split down by the plug. the wires cant be on wrong because it has a coil on plug system. the weird thing is it acts like a loose connection because it mainly does it after going around a turn.
but then it stops after it runs for a couple minutes.

I think I have it fixed. it hasn't done it sence I changed the fuel filter. but it may have just stoped doing it because it was pritty warm today. I'll find out for sure tomorrow.

 

[Lil' Shaun]

well I took it around the block thismorning. it was about 35-45 degrees out and the car ran fine. so I guess it was the fuel filter.

 

[_MACE_]

Nice.

 

[Lil' Shaun]

well it stoped doing it for about 3 days after the filter change. now its doing it again.