240sx weird idle

[todd5854]

My 240 is doing some weird stuff lately.

I'll start it up in the cold, and it will idle at around 1500 at first, then will drop to 500. sometimes 300-400.

My check engine light is on, as EGR malfunction. I replaced the intake manifold recently, maybe I replaced the vacuum lines incorrectly.

If I just remove the EGR system, would this idle problem and engine light just go away?

[davidoliva]

I would reccomend performing a leak down test, this will help to lacolize the problem. If you hear air leaking out the intake, its your intake valves, if its coming out your exhaust, its your exhaust valves, dip stick tube then its your rings, etc.

The most important thing is that they are all similar pressure ratings..

as in, you wouldnt want
1 at 190
2 at 195
3 at 120
4 at 190

[todd5854]

UPDATE:

The EGR code remains. Code 32. I reset the computer and on the way home the check engine light was flashing in a completely random sequence. No pattern..

[Josh@NSP]

You can remove the egr system, I remove it on many of the swaps I do. Car will run the same and wont even flash a cel if you block everything off properly.

[todd5854]

You can remove the egr system, I remove it on many of the swaps I do. Car will run the same and wont even flash a cel if you block everything off properly.

I've heard of that many times. But I was unable to find ANY information on how to do it, other than you need the block off plate. That's all I could find.

Also, it will fail visual inspection in PA I believe. I could be wrong.

[Josh@NSP]

Well, basically on the exhaust manifold you will find a large fitting and the egr pipe that wraps around the back of the motor to the egr pump on the intake side. It's as simple as removing the egr pipe and putting a plug in the port on the exhaust manifold and unbolting the egr pump on the intake side (a few 12mm bolts) and putting a block off plate in its place. If you need a visual I can snap some pics at work tomorrow. As for the visual inspection, I have no clue. I live in SC and we don't have any sort of inspection...

[davidoliva]

Sorry about my previous post, that was meant for another thread. Most 240sx's eventually have a problem idling. This is related to the IAA valve which control the air mixture during idle. The two options to fix this are to have a dealer adjust the valve or simply have it replaced.

The symptoms are clear: as you hit the clutch or lay off the gas and the car begins to slow and idle the RPMs may drop (sometimes quite rapidly) to extremely low levels, sometimes actually stalling completely. If this is happening have someone check out your IAA valve and you may wish to clean all the ground wire connections for the car's ignition and injection system.

[todd5854]

I seemed to fix my idle problem at the moment. If it acts up again I'll post it. But for now it's staying at or around 1000. I was so happy! My last 240 dropped to 250 - 400 at idle or with clutch.

As for the EGR removal... what do you do with those vacuum lines that connect to it? Just leave them there?

[davidoliva]

If your engine continues to idle real high after it's warmed up, check the air regulator unit. There's a hose connecting to it. Pinch the hose when your car is idling high. If the idle speed drops, there's a problem with the unit. Also check the electrical ground connections on the engine for looseness and oxidation.

[SoCal-S13]

I've heard of that many times. But I was unable to find ANY information on how to do it, other than you need the block off plate. That's all I could find.

reeeeeeeeeeeally. you couldnt find ANY info.

http://tech.240sxone.com/115/ka24de-egr-removal/
http://www.nicoclub.com/archives/intake ... embly.html
http://www.google.com/url?sa=t&rct=j&q= ... M61SAszslg

according to google that took .095 seconds. you need a block off plate and and egr plug or as Nissan calls it an egr plug taper OEM Part# 14052-21R00. Available at every single Nissan dealer in the US.

Also, it will fail visual inspection in PA I believe. I could be wrong.

I could be wrong.

wrong.

[Josh@NSP]

Vacuum lines get plugged. Some people put a bolt in the hose, some people put a nipple on it. Just don't leave them open.

[todd5854]

Socal, if you read my post, i said the same thing you did about needing the plate...

Thanks josh for actually answering the question thoroughly.