P0402 - Q&A (1 Viewer)

[musthave]

Experiencing P0402. I've decided that I don't want to do any of the workarounds, I want to fix it.

Searched a lot of threads over the last few days. Here are some questions, need answers.

• Is the port from the EGR valve to the VSV clogged? - How can I determine this? I'm not sure how to identify the EGR valve vs. the VSV.
• Replace all vacuum lines - Read several posts about vacuum lines that are the wrong size. Is it better to just buy them from Beno?
• I'm told that the 1.5" tube resolves a lot of the P0402 codes - Where is this 1.5" tube they speak of?
• Pull EGR temp sensor and clean with brass brush - Where is the EGR temp sensor? Same as the EGR valve?
• The hardline that goes through the air intake manifold had plugged, cleaned with a piece of non-stranded wire - Where is this "hardline" they speak of?
• Bad cat gasket - Where is the cat gasket?

Is there any diagram that shows where these things are? Like a P0402 Diagram? If not, when I'm finished I might make one up, appears to be needed.

I'd appreciate anyone's help with these questions.

 

[94SRUNNER]

Do you have a FSM (Factory Service Manual)? If you do, then that is the place to start. There should be a diagram on the underside of the hood that has the layout of the EGR system. Check there.

As for the part location questions, I don't have the ability at the moment to pull together a picture(s) with the locations of the parts in question. But hopefully someone will chime in. However some on the threads on the 402 code, might have pictures with locations.

If you can get a hold of factory vacuum line from Beno, then tell him what you are up to and he will get you the correct amount. It is a matter of removing one line at time, measuring, cutting, and replacing them.

The EGR temp sensor is located at the back of the intake manifold on the drivers side. It has a wire coming off of it and is held in place by a 14mm bolt.

The "hard line" does run through the top of the manifold and to clean it, it probably best done by removing the top half of the intake manifold. This will allow for the best access.

The EGR valve is located at the back of the head on the passenger side and mounts to both the head and intake manifold. Check the diagram on the on the hood.

I am not sure about the 1.5" tube or the cat gasket. Those are new to me.

Good luck.

 

[freemasonralph]

Help ... Please! CEL from H E L L... 1996 Land Cruiser

I am chasing CEL's for a long long time. I had the P0401, then a P0420, then P0401, and then P0420, now P0402
I do not have a FSM for the 1996 Land Cruiser - if someone has an electronic copy that can be emailed - or downloaded I would be grateful

I first replaced EGR Valve, the EGR vacuum pump then the relocated the EGR Vacuum switch and used the cheaper switch that someone recommended from AUTOZONE - nice thing is that has a lifetime warranty so I replaced it once already.

I got the CEL off for 3 days, 1500 miles. then it came on and I ignored form many months - tried again so I can drive with legal plates.
Replaced all 3 components again - no luck at all... but got a second new code P0420 - had a crack in y pipe by headers - little muffler paste and it went away and then the P0401 came back... took off throttle body cleaned the port - it was CLOGGED - cleaned the passage from port to EGR - cleaned EGR - replaced most of the vacuum hoses... cleared the codes (pulled battery power) got the p0420 code again - this time a crack in the pipe where 2 pipes joined right after catalytic converter but before O2 sensor. Fixed that - reset codes again, P0420 came back again ... replaced the Catalytic Converter ... $78 at adv. auto + $60 to put it on. Cleared codes again and the damned CEL came on with P0402... so I went from have insufficient flow to too much flow on the EGR...

I am at a complete and utter loss ... I have expired plates and I Drive 150 - 250 miles a day....
Could use help - guidance - and a cold one.....

Thanks

 

[txgringo]

sounds like the P0402 is still the top PITA on the 80. I'm now troubleshooting one as well and was looking to see what others are doing about it.

I have no advice/wisdom to share as of yet, butn my search I found the following post which has several FSM's available for download:
https://forum.ih8mud.com/threads/40-50-60-and-80-series-fsm-for-a-hell-of-a-price.610994/

 

[musthave]

I've never resolved mine. I just reset it every few days or give.

 

[AZ4ME]

Did you check the hard port that goes through the intake manifold? They tend to get clogged with carbon and throw P0402 codes. This was my resolve for my P0402 code. And it's free.

https://forum.ih8mud.com/threads/p0402-learn-from-my-mistake.132135/

 

[izzyandsue]

This is funny, but not really. I have been doing like Tim, I keep a cheap code reader/rest tool in truck and reset it every 100-200 miles. The $49 tool is cheaper than the fix could be, some silly solenoid under intake that will cost me over $200 to get done. And I have the tool to share with others on the trails....