dcorazal

I have a 97 path with 140,000 miles, runs great and still gets good mpg. Cold starts are fine, but after the engine is has been running and it sits for 10 minutes to an hour it starts hard. I need to press the accelerator slightly to get the engine to start. I has been a while since the last tune up, may be 50,000 miles. I replaced the plugs, (NUMBER SIX WAS NOT FUN!) they didn’t look bad and did not fix the problem. I have the other tune up parts on order ( wires, cap&rotor, pcv, air filter, fuel filter) and am running some injector cleaner through a tank full of gas.
Just wondering if anyone has any advice or insight, I searched all the forms and didn’t get any help so far. Any thing to look for. CEL is not on.
Thanks

 

dcorazal

Update: Tune up didn't help.

Does anyone know if there could be a code that is triped without the CEL on. I'm thinking I may have a sticking injector?

dvdswanson

check the MAF, IAC, and TPS. then I would check the fuel pressure, for the pump and regulator.

__________________
Dave
96 4WD XE Reg. Cab ka24e
Calmini 3" SL, Steering, Lock-rite rear, LSD front

dcorazal

Thanks for the reply:

I pulled out the MAF and cleaned it with electrical contact cleaner. No luck

I went to Autozone this morning and had the OBD read and got a P0325 (Knock sensor)

Could the knock sensor cause hard starting?

I noticed the hard starting has happened when cold but only ocationally.

dvdswanson

yes a knock sensor can cause hard starts, check your connector too. who knows you may have had a little friend try to dine on the wires.

__________________
Dave
96 4WD XE Reg. Cab ka24e
Calmini 3" SL, Steering, Lock-rite rear, LSD front

 

dcorazal

Finally getting around to working on this problem: I have had the CEL come on and through a P0300 (engine misfire). Hard starting when warm is still the issue.
I bought a fuel pressure tester and performed a fuel pressure check per the manual.
Here’s how it went.
1: Removed the fuel pump fuse and let engine die, and then cranked the engine over several times. Removed the fuel line from the rail and gas shot all over. WTF I guess there was still pressure in the line.
2: Next: When I pulled off the vacuum hose from the fuel pressure regulator to the manifold there was gas in the vacuum line????? Could the fuel pressure regulator be internally leaking?3: Ran pressure check and pump with regulator disconnected was at 43psi like to should be. Then connecting the external vaccum source to the fuel pressure regulator was able to get the pressure down to 34psi like expected.

Someone please tell me that the fuel pressure regulator vacuum line should not have fuel in it.

golfer

I would think it's safe to say there should be no fuel in a vacum line.
Btw... with the gauge installed did the pressure hold for a while when the engine was turned off ??

Check this thread from someone with an X-trail having " hot soaked " starting issues.http://www.nissanforums.com/x-trail/...ot-soaked.html

dcorazal

The guage did hold for a while, maybe 15-20 minutes. One web site i found said the pressure should hold over night. I did a search on google and found this Troubleshooting Electronic Fuel Injection Problems it clearly states to look for fuel in the vacuum line. The leak in the diaphragm must be small but big enough to cause the problem. I'm ordering a regulator today. This is going to be a project. The Throttle body has to be removed to get to the regulator. I'll keep this thread going untill Its fixed.

dcorazal

Fixed!!!! Fuel Pressure regulator took care of it. Starts perfect now. Removing the manifold was not that bad of a job.
Hope this helps some one.

dvdswanson

thanks for the update.

__________________
Dave
96 4WD XE Reg. Cab ka24e
Calmini 3" SL, Steering, Lock-rite rear, LSD front