engine problems

[sniperbill3]

i just redid my 90 240sx straight up from the ground and now it is having performance problems it just doesnt have any power there are other things wrong such as i need a new alternator and a fan but everything else is fine the fan just has 2 blades off of it and that is all but the car has been sitting since 2001

[sniperbill3]

i think it is the throttle position sensor because it revs up and down when you start it and i also have a custom exhaust header on it and 3.5 inch straight pipe back from the header with no cat or resonator and a stock muffler but i also think that it might be the o2 sensor

[foress_89]

It's very hard to guess just like that. When you say you've redone your 240sx from top to bottom, what does that means? Did you even pull the engine? As for the alternator not working, it could be just that. Or it could be a vaccum leak, what about your air intake? Give us some real information.

[tero404]

my car is running like *** too but for u, u have to narrow ur search3.5 inch exhaust on a l4 non turbo engine is kinda over kill imo buti bet it sounds cool and shoots flames anyway..

what does ur spark plugs look like?what do they smell like?whats coming out the tail pipe?are ur valves correctly adjusted?could it be a ecu problem?could it be a injector problem?u said ur alternator and fan are bad... this may sound like a sillyquestion but are ur belts tightened correctly?

[sniperbill3]

yeah it sounds really cool but i redid the engin like pulled it and redid it because it had blown head gasket but even , ive checked vacum and it is fine and so is distributor and coil pack as long as everything else but the injectors are sticking ans i think maybe it could be the fuel pump not putting out enough pressure

[DubsSuck]

3.5 stright pipe!?!?! thats huge!! too huge if you ask me, unless its boosted. is it?you need back pressure to push off of that may be why its not running right.

[sniperbill3]

no boost but i have the stock muffler on it and it has some back pressure and it should be enough and i am sure that is not why it is running like that

[sniperbill3]

the injectors had trash in them when i first got it running about a week ago and i got new ones and then it would actually run right now the 2nd injector leaks but that is from a bad o ring on it and the fan has 2 blades broke off but that was from running over a stick and the alternator isnt charging at all

[sniperbill3]

i meant running not running right

[DubsSuck]

no boost but i have the stock muffler on it and it has some back pressure and it should be enough and i am sure that is not why it is running like that

haha you'd be suprised...you could take off the whole fan and it would still run just fine. so thats not a big deal.my suggestion: get a resinator. new parks and wires

[sniperbill3]

i have brand new spark plugs and wires and i and going to put a resonator on it tomorow

[DubsSuck]

i just relized that resonators make the pipe bigger.. im sorry i miss spoke. you might want to try getting just a smaller pipe

[sniperbill3]

ill try but i really think it is the fuel pump not putting out enough pressure to close the injectors at the right time

[tero404]

there are 2 fuel lines on da intake manifold, borrow a fuel pressure tester from a friend and hook it up into ur fuel lines and check to see if ur pressure is in spec (i dont know the spec)

if its not in spec, change ur fuel filter and borrow a friends fuel pump and see if that helps and if ur fuel pressure is in spec

[mmaxeyjr]

if its reving up and down i would check the IACV also MAF

any vacuum leaks?

[sniperbill3]

no leaks but that is a good idea for the pressure prob ill see wats up

[DubsSuck]

Back pressure!

[sniperbill3]

tried the back pressure from the exhaust and guess what , that was not the problem it is still doing the same thing

[mmaxeyjr]

check you injectors, check timing (at distributor, and shine a timing light to make sure it's right). Also check all around the engine bay for vacuum leaks or any leak of any kind. Make sure all wiring for corrosion etc. Clean all plugs and connectors with a wire brush to take off any build up causing a poor connection.

Also check for exhaust leaks etc. etc.

Try unplugging the battery for a day (resetting ECU)

Seafoam...

Cheapest stuff first. If none of that fixes it, you're S.O.L

[tero404]

well my gf says u should give up and by a new car, but did u put ur distributor in right after u took it out? that could cause ur car to run bad

[sniperbill3]

i fixed the problem like i said it was the fuel pump now it hauls ***