Thursday, March 27, 2008



*Automotive Rant* - and blogspot is messing with my paragraph formatting... great!


Photo: Billypalooza

This little light is a vast irritation. Sunday it came on, then went off. Came on again. Went off again.

So I get out my trusty diagnostics tool (thankfully on the older Toyota's all you needed was a paperclip) and discern the trouble code by reading the morse code of flashing dash lights... Code 71!

Go to the greatness that is the Internet and look up the code to find that it is my EGR system. So I unplug and replug the connector to the EGR system, I notice that there is some bare wire showing (filing this information as a possibility of the problem). I disconnect the neg. battery cable for a few minutes to clear the code, and then fire up the truck.  HEY the light is gone! Hooray!

Two days later it turns back on.... So now the list of things running through my head are: tank of bad gas (the whole things started a few hours after filling up), bad temperature sensor wire (as observed earlier), EGR valve stuck open, or bad ECU.

For now I have disabled the EGR valve (by simply blocking off some vacuum tubes with screws), which has definitely increased the performance of the truck (leading me to believe that the entire valve is bad). Of course this doesn't make the check engine light go off, since the temperature sensor has nothing to do with the actual operation of the EGR valve.

So if the light continues to stay on after my next fill-up, I will be shoving a resistor into the plug to at least get the light off, and then order the 2 parts necessary to fix the system, at a price of over $200.

Of course, I could leave the system jimmy-rigged with a resistor and plugged hoses, but that may cause a problem with engine temperature in an engine that is already known for having heat-related head gasket issues. Plus it's bad for the environment...

Sometimes I love working on my truck, but this is not one of those times.


Kitty said...

Can you hear the loud *whooooooooooooooosh* sound as all that truck talk goes over my head? :-p

As for the Blogger formatting - if you go into 'Edit HTML' and ensure that you have < p > before each paragraph, and < /p > after each paragraph (only close the gaps - Blogger won't let me post it in the comments section without the gaps), it should sort it out for you.


Catalyst said...

Tombo, I think I see your problem. Your old truck is still running on vacuum tubes. You need to buy one of the new transistorized models.

You're welcome.

TomboCheck said...

Kitty - Oh, the < p> is in there in my software (windows live writer), but sadly it decided not to transfer it to blogger when publishing. And I am SO not motivated enough to go into blogger and fix it there. :) I'm a lazy bastard.

Catalyst - Tell me about it! And the freakin vacuum tubes are always going out, I have to keep a box of them in my truck. :)

Chickenbells said...

ohhhh...I hate car troubles. Although, once when we took the Trooper in because the "check transmission" light came on, they told us it was a $75 problem with the light itself, and put some black electrical tape over it. So, you could always do that! (hahaha...really, I think it's always better to fix the problems with just saves in the long run)

TomboCheck said...

Chickenbells - Normally I don't mind working on my truck. But I hate hunting down electrical issues.

And instead of electrical tape, it is looking like a twenty cent resistor is going to get shoved into a connector to turn the light off. :)

Anonymous said...

EGR valve is designed to burn a little of the exhaust gas to reduce oxides of nitrgeon (nox). Leaving it dis-abled will give you better performance but could cause pinging. If the engine is equipped with a knock sensor (it probably is)it will retard the timing to eliminate the ping which will then reduce your performance. Catch 22


TomboCheck said...

Dad - good to know. The engine is equipped with a knock sensor, though I have yet to hear any pinging. Isn't the EGR also designed to reduce combustion chamber temperatures (by reducing the amount of combustible oxygen in the cylinder)?

Over at Yotatech there are lots of folks leaving the systems disabled (or removing them entirely and installing blocks over the egr ports) with no apparent negative performance effects. Keyword being apparent of course.