jkerton

new poster here. have a 98 C4 platform Quattro Avant witha 2.8 V6. have a code 1408 which is "EGR temp signal too high". Would you say this is a bad sensor or an EGR that is, lets say always on, passing gas and raising the temp, signalling the high temp code. Where is the sensor anyway. Any help is appreciated. Have to clear the code, which I did twice and is back again. Regi is up end of Jan and need to get the emissions done before then. Thanks.

DaveInSaltLake

the FAQ, which is linked near the top of the page.

It's a common problem with several possible causes and fixes that are all discussed at great length in the FAQ.

Any pics of your car?

austinado16

Welcome! Avant's rule. lol...you said, "...passes gas...." You'll fit right in here!

jkerton

I knew that might get a rise. Lol! I have been on many discussion forums and little funnies like that seem to aid in the iniation to the rest of the group. I am also on the BMW forums as well.

jkerton

I will get some pics for everyone. I was specifically asking about that code and fault message because I didn't really see it addressed in the search archives. Only the 0401 EGR low flow due to the clogged passage. In my case the I'm not getting that, although I've had that before and I think I fixed it by repairing a cracked vacuum hose up near the hose bundle near the actuator area under the MAF. I'm getting the 1408 code that says EGR temp sig too high. Can that only happen if egr is continually open. Or is the sensor faulty? Where is the sensor and does anybody have a picture? Thanks.

DaveInSaltLake

the DIY about cleaning the EGR passage in the manifold then you're somewhat familiar with the area. The passage starts where the EGR valve is ported to the manifold and runs straight, horizontal for a couple inches. From there it actually tees vertical to the inside of the intake manifold. The 3rd leg of the tee continues horizontal another inch or so to the temp sensor. I believe the temp sensor can be removed with a wrench from the PS of the manifold. I'll look around for some photos.

jkerton

Thanks. Do they go bad? Would the fault" EGR temp signal too high" be indicative of a bad sensor, or is it doing its job pf detecting something out of range, meaning a high temp. What would make the passing gas/air temp higher than normal? Can an EGR that is always open cause that? Can the gasses that pass be any higher than its hottest temp. It's exhaust gasses that pass through the passage right?
Thanks

DaveInSaltLake

on the driver's side of the motor.

DaveInSaltLake

first is from the A6 manual for the AFC motor. looks like the temp sensor is on the drivers side:
<img src="http://i100.photobucket.com/albums/m32/JunkyardCars/misc/EGRTemp.jpg" border="0" alt="Photobucket">

2nd is from the A4 AFC manual. This looks more like what I remember:
<img src="http://i100.photobucket.com/albums/m32/JunkyardCars/misc/EGRTemp2.jpg" border="0" alt="Photobucket">

jkerton

Thanks for that Dave. Have you found any to be bad?