Engine Quit with Electrical Burning Smell

[rgk]

I'd say your IAC, VVT, and EVAP issues are all unrelated.

Test your VVT and EVAP vent solenoids for proper operation by removing them, applying 9v voltage, and listening for a click for the vent control and watching for piston movement in the VVT solenoid.

[4xq]

One of the causes of P505 is a large vacuum leak, and your P0455 "Gross leak" may be the vacuum leak that is causing that. So I would go looking for your evap system vacuum leak and see if the P0505 goes away. One would hope so with a new idle air control valve.

[pstarbard]

I checked both solenoids using 9v and they seem to be working correctly. Got the Audible click for each and could see the valve move in the VVT(canister vent control valve). I'm guessing this means they're both good. Where to go next?

Áa side note, it seems that these parts are each called by several different names and that's causing some confusion.

[pstarbard]

I think the only things left are:

- EVAP pressure sensor
- vacuum cut valve
- vacuum cut valve bypass valve
- charcoal canister
- a leak somewhere else in the system

Any ideas on how to confirm our eliminate each of these as the source of the problem?

Thanks,
Al

[rgk]

The variable valve timing solenoids (there are two) are different from the canister vent control valve solenoid. The VVT solenoids are at left and right banks of the engine in the front, are cylindrical, and will have oil dripping from them.

The vent control solenoid is (I believe) located near the throttle body, atop the intake plenum, and looks more like a traditional solenoid.

[pstarbard]

Based on your description, I checked the vent control solenoid but not the VVT solenoid. I'll check those next. Thanks.

[Buzzman]

One of the causes of P505 is a large vacuum leak

I have never seen this code generated by a vacuum leak.
For what it's worth, I think your 3rd party IACV blew, taking the ECM with it, again.
In my mind, there are certain things that I would spend the extra money on and buy from Nissan (OEM).
One of those is the IACV.
All those evap codes are a red herring, in my humble opinion.
Take the IACV out and see if it moves under power. If it's stuck shut, then that will cause your stalling.

[pstarbard]

Problem is that I've had the vacuum leak code for quite a while. Long before the IACV went the first time. What you say about the IACV being stuck makes some sense. When i first encountered the idle problem after installing it i was able to "fix" it by holding the throttle open while someone else started it without touching the gas peddle. Then it would be fine for a few days before the problem would come back. How would I go about testing the IACV after I remove it?

Thanks,
Al

[rgk]

So, I tried the re-learn procedure and it didn't fix the problem. The engine still won't idle unless I give it a little accelerator to keep the RPMs at 500 or better. I checked the codes and found the following:

P0505 - Idle Air Control System
Probable Cause: Large vacuum leak, engine mechanical condition or failed IAC valve.

P0455 - EVAP control system gross leak detected (I've had this code for more than a year, way before the IACV and ECM problem that started this thread, and it comes back after being reset)
Probable Cause: Faulty fuel cap (got a new one and problem didn't go away), purge system leak, faulty canister vent control valve or faulty purge control valve.

P1448 - EVAP canister vent control valve (open)
Probable Cause: Failed canister vent solenoid or failed EVAP pressure sensor.

P1140 - Intake valve timing control position sensor (left bank)
Probable Cause: Open or short circuit condition, poor electrical connection, failed intake valve timing control position sensor.

P1110 - Intake valve timing control (left bank)
Probable Cause: Open or short circuit condition, intake valve timing control position sensor fault or blocked signal due to debris.

Based on this, I could replace any/all of the following parts:
- canister vent control valve
- purge control valve
- canister vent solenoid
- EVAP pressure sensor
- intake valve timing control position sensor
- idle air control valve (already replaced this once)

Any ideas on how to narrow down the failed part? I suspect it's one part and all the other codes are cascading from that.

Thanks,
Al

Let's not get confused here.

0505 - this is your main idle problem. If you are concerned that a large vacuum leak is causing it, check your vacuum pressure. If you have good vacuum, then vacuum is obviously not the culprit.

0455 - this is a FUEL VAPOR (EVAP) leak, NOT a vacuum leak.

1448 - EVAP vent control valve open

1140 - Variable valve timing (VVT) issue. My book says right bank.

1110 - VVT issue, right bank.

Trust us when we tell you that your EVAP and VVT issues are not causing problems with your IACV.

Double-check to make sure your IACV is properly connected.

[rgk]

To test the IACV, remove it and apply 12 volts to the leads. Like a solenoid, if it doesn't open with voltage applied, it's stuck.

[pstarbard]

Does it matter which lead I apply the voltage to?

[pstarbard]

I removed the IACV and want to test but there are six pins/leads. To which lead(s) do I apply the 12v power?

Thanks,
Al