95 240SX KA24DE Bucks - Sputters - Loss of Power -

ONLY for ADVANCED technical discussion about the 240sx!
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AzBrewsky
Posts: 18
Joined: Sun Jul 05, 2009 1:42 pm
Car: 95 Nissan 240SX KA24DE 5-Spd

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I have an issue very similar to this post - (forums.nicoclub.com/zerothread/295236)
RamonetB wrote:My car is losing power and feels like it's not getting enough gas, and bucks when i try to accelerate.

The quick and the short:

3 weeks ago, during a normal in town drive, the car starting bucking just like when someone doesn't know how to drive stick properly. Eventually she died and wouldn't start. She'd turn over, but never "Catch". I had it towed and was told that I had no pressure on the fuel line.

Replaced the fuel pump.

Car works great for 2 weeks.

Then, all of a sudden, it starts bucking again. But this time things are a little different:

It never actually stalls and dies.

If I turn it off, she'll start right up.

When driving, it usually takes about 30 minutes before the bucking starts. Once it does, it's minor, almost like hitting a rumble strip. Then it gradually gets worse. This whole time there is a loss in power and accelerating exasperates the problem. Eventually, I can't even maintain speed without bucking. Then, I can't even give the car gas while going downhill without it bucking.

When idle after these events, it idles very low and very erratic.

Now here's the strange bit: If I turn the car off and let it sit for 30 seconds to a minute, she operates normally for about another 5 to 10 miles and the process repeats itself.

WHAT'S GOING ON? Is the fuel pump that was replaced defective? Is it overheating and therefore not operating correctly?

Is there a ground somewhere I should check? Before all of this happened, I put a new heater core in, which meant removing the dash and disconnecting a lot of the interior wiring harness. I hooked everything back up, but is there a ground in there I didn't tighten correctly or something?

Any help, please! I'm really confused on this one. <IMG NAME="icon" SRC="http://images.nicoclub.com/forums/image ... /anger.gif" BORDER="0">

-kirk

P.S. It seems to take longer for the events to happen when it's cold out vs when it's warm out. (IE, 30 degrees vs 45 and up).
However there was no solution to this problem.

My issue is the same.. After looking at possible problems (see below), I drove it from Phoenix to Payson AZ (about 90 miles, and elevation change of about 3000ft) early in the morning with no issues. Next day I drove back to Phoenix and started having the problem. If I pulled over while the problem was happening, I could floor the accelerator and the engine would sputter and the RPMs would bounce between 1500 and 3000. While pulling to the side of the road twice (did it about 10 times), the car stalled but would immediately start back up. Once I got to the Phoenix area, I stopped and had lunch. About 15 minutes later I got in the car and drove about 15 miles home and the problem didn't happen again..

So...

What I have done (with help from my friend Dan, a Mitsubishi mechanic):

- Checked fuel pressure and it showed 56lbs coming in, and the return line showed 4lbs at idle. I even had the gauge taped to the windshield while it was connected to the return line and drove it around. The pressue dropped to 0lbs when I was accelerating, but unforturnately the problem never happened. Pulled out the fuel pump and inspected the tank and it was clean. Dan had me turn the key to the on position (but not try to start) to listen to the fuel pump. It spun up just fine, and as you can see from the pressures, it pumps fuel just fine.

- Checked MAF screen. Looked clean, and all connections are tight. We thought maybe the engine wasn't getting enough air. The air intake scoop (which was not bolted down) showed marks on the hood where it looked like it would get sucked up and cause less air.. Less air would lead to believe the computer would see it and provide less fuel. Removed the intake scoop so air would suck directly into the elbow to the air filter. Air filter clean!

- Spark Plugs: Changed spark plugs a while back, but Dan says if it were the spark plugs it would do it all the time. Spark plug wires are about 3 years old. Haven't looked at the plugs themselves yet...

- All fluid level are good. Although I don't see any smoke coming out the tailpipe, it does seem to go through oil. When the car sits, there are quite a few oil spots on the ground.

- Ran injector cleaner with a tool that connects directly to the hose at the fuel rail. Ran the engine until the entire can was emptied.

My car has 136,000 miles on it. And other than the issue here, it runs fabulously!

Any help would be greatly appreciated, and thank you in advance!!

AzBrewsky


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moso
Posts: 801
Joined: Sat Jul 04, 2009 5:14 pm
Car: 89 240sx ka24de 5spd
90 240sx ka24de RIP

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i dont know if this is gonna help you but you can give it a shot. i had this problem with my f150, it has a 300 6cyl, it would run fine for a short time then it would start bucking and trying to stall out and it all seemed to happen only after it warmed up. it was the egr valve. to check it i was told to unplug the vacuum line from the top of the egr valve and plug the line, if your problem goes away you have found your problem, if not then just plug it back in. not garunteed to work but alot better than sitting on your thumbs.

good luck.

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AzBrewsky
Posts: 18
Joined: Sun Jul 05, 2009 1:42 pm
Car: 95 Nissan 240SX KA24DE 5-Spd

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Thanks for the response. I will give it a try..

michacl240sx
Posts: 2
Joined: Wed Jun 16, 2010 5:36 am
Car: 91 nissan 240sx

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i have replaced the egr valve but the problem still excits. it still loses power when i press the gas n only happens when its hot. i also have noticed that once i turn the key off n than on again the problem goes away for awhile than starts again after 10minutes or so any help well be great thanks

michacl240sx
Posts: 2
Joined: Wed Jun 16, 2010 5:36 am
Car: 91 nissan 240sx

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okay so do day i did a fuel presure test hooked up the tester n took my car for a spin. as it warms up n starts to loss power i saw the fuel pressure gauge drop from 35psi to 10psi. which means that the fuel pump is acting up as it warms up. end up replacing the fuel pump and differents was noticable.

con.way
Posts: 1
Joined: Wed Aug 06, 2014 3:38 pm
Car: Clean s13 ka24de
Raptor 660
Seadoo gtx

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Please tell me you found this problem out! I'm stuck

RayjunBohner
Posts: 5
Joined: Sat Jan 25, 2014 4:59 pm
Car: 1990 240sx RB20DET
2009 Altima :)

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Checked fuel filter?


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