I bought a 91 240 a while ago and I got a problem i cant fix. After 5500 Rpms My car cuts out, the rpms rise but theres no real speed increase. I have a friend with a s14 and a friend with a s13 coop they were both the same upgrade and moters as mine but they pull really hard on me. Also my idle bounces alittle from 500 to 1000 not hard tho. I have tryed cleaning injectors with the gas treatment shit no luck, i put new wires on plugs and still no luck.It also hesitates alittle when i step on gas. the motor runs fine has 143,000 on it. I have also changed fuel filter too. i have good air filter too. ANY IDEAS AT ALL NEED HELP ! could it be vac hoses?I forgot i also pop a flame when i change gears at 5000 and up.




fellow 240sx owner.

 

search

 

So many people have idle issues and this is the most common solution. It took me about 30min to do but I have small hands.

Here's the IACV:
http://www.geocities.com/motorcity/...ay/5167/iaa.jpg

The pic is taken from the rear. To find it from the passenger side, proceed to the end of the intake manifold and look under the EGR piping.

0. Remove vacuum line.
1. Disconnect IACV-FICD harness (purple, be careful).
2. Unscrew IACV-FICD solenoid (don't drop anything)
3. Remove 10mm bolts (there are 4).
4. The 4th is under the solenoid in the pic.
5. Remove gray connector harness.
6. Remove IACV housing, clean w/ carb cleaner. Remove idle adjustment valve and clean out as well.
7. Gasket will crumble apart. Scrape away all residue.
8. Carb clean inside the manifold port, wipe away with cloth.
9. Re-gasket and re-assemble.

Adjust Idle:
1. Have the car warmed up
2. Disconnect the TPS harness
3. Turn the idle adj. screw on the IAA to get the car to idle at 650 rpm.
4. Reconnect the TPS harness and your car should purr at 700 or so rpm. (The Factory manual gives a +/- tolerance of 50 rpm).

Hope this helps you all out,

Jesse

CUT AND PASTE FROM THE OTHER POST.

Hope that helps

RINKU

 

The thread i refferred from is here

https://www.tamparacing.com/forums/s...highlight=iacv

RINKU

 

Certainly Rinku's how-to on the IACV is very valuable. I pulled all kinds of nastiness from mine with only 100k miles. Belching flames is another story, though. I also agree with Ostrich that a search should be done, but this is sort of a tricky thing to search on.

Here's a clue for you, engine detective: You're running rich. Things to check are: vacuum leaks, intake leaks, faulty MAF sensor, and FPR has vacuum.

"Give a man a fish, and he knows where to go for fish. Teach a man to fish, and you've ruined your market base" or something

 

I switched the MAF last night with a friend and its not that. Whats a FPR?

 

fuel pressure regulator. def check all of your vaccum and intake. my car hesitates horridly bad and thats because my intake is about cracked in half

 

How do you check if fpr is getting vaccum ?