EGR CEL light.. new EGR valve and Modulator installed ?..

[40thSagePearl]

I just bought this 1996 LX450 about a month ago and received receipts with the truck stating it had the EGR valve , modulator, and hoses replaced less than a year ago. I recently received a check engine light and my mechanic told me its throwing a EGR code.. Told me to just drive it and see if it goes away perhaps it is clogged up. This seems odd to me as it all seems to be new though.. anything else i should be looking at or cleaning ? thanks guys !

 

[Grod302]

Probably the VSV to be honest with you. I gotta replace mine

 

[Landseer]

Toyota only installed the EGR system for US trucks and it's known to trip the CEL for basically no reason. You can wire a resistor into the EGR temp sensor to prevent the CEL.

 

[Grod302]

Toyota only installed the EGR system for US trucks and it's known to trip the CEL for basically no reason. You can wire a resistor into the EGR temp sensor to prevent the CEL.

Landseer could you elaborate more on this? I gotta have no CEL on my truck in order to pass Virginia Emissions

 

[Landseer]

The CEL is tripped due to insufficient EGR temp, you can unplug the temp sensor from the harness and wire in a resistor (I believe 20k ohm) it then tells the computer the temp is high enough and you don't get a CEL. The temp sensor's only function is to trigger the CEL so the EGR system is unaffected. Toyota realized the EGR system was too sensitive and likely to cause CEL for no real reason and made a part that shorts out the temp sensor for the 93-94 trucks, that part doesn't work for the later years but many people have had good luck with the resistor mod for the later years.

 

[Grod302]

The CEL is tripped due to insufficient EGR temp, you can unplug the temp sensor from the harness and wire in a resistor (I believe 20k ohm) it then tells the computer the temp is high enough and you don't get a CEL. The temp sensor's only function is to trigger the CEL so the EGR system is unaffected. Toyota realized the EGR system was too sensitive and likely to cause CEL for no real reason and made a part that shorts out the temp sensor for the 93-94 trucks, that part doesn't work for the later years but many people have had good luck with the resistor mod for the later years.

Are there any write ups or threads on what plug I need to do? I am really interested on doing that

 

[Landseer]

EGR Readiness Achieved with EGR Removed!
EGR code P0401 - correct resistor for "trick"?
'94 Code 71, EGR Bypass and redneck technique..

When I did this on mine I used an old ERG temp sensor I had lying around and cut the temp sensor off and shorted the wires (for 93-94 you only need to short the wires for later years you'd wire in the resistor instead).

 

[MtnCruiserFZJ80]

Likely the VSV.. That required one hell of an ratchet extension, because I didn't want to remove the TB. You could also have a clog somewhere. I had a chunk of carbon built up after I hit my vac lines with sea foam, which triggered an EGR CEL.

 

[40thSagePearl]

Likely the VSV.. That required one hell of an ratchet extension, because I didn't want to remove the TB. You could also have a clog somewhere. I had a chunk of carbon built up after I hit my vac lines with sea foam, which triggered an EGR CEL.

funny you mentioned sea foam.. was thinking about doing this myself but have never used the stuff, only read about it. I have put some fuel intake cleaner into the gas tank. my truck idles and runs PERFECT; whisper quiet. so im confused as to why im getting this CEL light. Perhaps my culprit is the VSV, any recommended way to test this so i can tell my mechanic ? i plan on replacing all those little vacuum lines too if necessary

 

[Grod302]

I just got my VSV replaced yesterday and also filled up the truck with Premium fuel. did a fuel induction service while replacing the VSV and she runs smooth as silk, no CEL (yet) and idles really smooth. hopefully that did the trick

 

[MtnCruiserFZJ80]

funny you mentioned sea foam.. was thinking about doing this myself but have never used the stuff, only read about it. I have put some fuel intake cleaner into the gas tank. my truck idles and runs PERFECT; whisper quiet. so im confused as to why im getting this CEL light. Perhaps my culprit is the VSV, any recommended way to test this so i can tell my mechanic ? i plan on replacing all those little vacuum lines too if necessary

P0401 - EGR flow insufficient – HOW TO… - Club Lexus Forums



RMLCA - Rocky Mountain Land Cruiser 4x4 Association

Here's some stuff I had bookmarked from my EGR battle. The only downside is the VSV is a real SOB to get to.

Sea foam may help for insufficient flow due to clogs and funk, but won't help if your sensors or valves are bunk.

If I remember correctly, the insufficient flow egr code is 7-1.

 

[40thSagePearl]

P0401 - EGR flow insufficient – HOW TO… - Club Lexus Forums



RMLCA - Rocky Mountain Land Cruiser 4x4 Association

Here's some stuff I had bookmarked from my EGR battle. The only downside is the VSV is a real SOB to get to.

Sea foam may help for insufficient flow due to clogs and funk, but won't help if your sensors or valves are bunk.

If I remember correctly, the insufficient flow egr code is 7-1.

Bringing up an old post.. my mechanic cleared the codes. I ran royal purple cleaner into my fuel tank, was CEL free for around 600 miles.. then boom. I have the engine idling in the parking lot and I see that Damn Orange light come on the dash. I'm going to clean the MAF sensor and order the VSV aswell.. Seems like it's going to go bad some day anyways ( if it isnt already ) so might aswell replace it now. I need my truck fixed !! Snows on its way !

 

[MoJ]

Test the vsv as instructed in the fsm. All you need is a cheapo harbor freight meter.

 

[MoJ]

Toyota only installed the EGR system for US trucks and it's known to trip the CEL for basically no reason. You can wire a resistor into the EGR temp sensor to prevent the CEL.

There's ALWAYS a reason for the CEL.

 

[MtnCruiserFZJ80]

About 1k mile after my CEL went off after replacing my VSV and egr modulator, mine came back on due to carbon deposits on the temp sensor. Make sure you clean that off as well while you're trouble shooting.

If your problem is just a really bad build up of deposits, one run of cleaner may not be enough. You may need to do several courses of cleaners/Italian tunes ups for it to make much of a difference. Additionally, this may trigger a CEL if those deposits end up on your sensors or block up one of your hoses, etc.

Good luck.