I have read quite a few threads regarding glowing turbos and precats, down pipes etc...including Kahren's post with respect to glowing at idle...some suggest this is normal..others suggest a rich fuel condition..while still others remark this could be airpump related

Here's my situation, the front part of the turbo housing is glowing, I assume this is the primary. This occurs on start up. While attempting to get the idle to lower ( for a few minutes), I noticed the whole downpipe as well as the turbo housing glowing. Again this is at idle about 2100 rpms, not after boosting but when starting the engine from cold and subsequently warms up. Another piece of info..the main cat is also not connected.

Originally, I thought I had a clogged precat, so I replaced it.

Mazda has diagnosed this to be a bad set of twins, are the twins the root cause?

Any comments would be appreciated.

thanks

 

list mods, mileage, original engine/turbos? please.

why are you idling at 2000?

 

Your in St. Louis, take it across the river to Bistate Customs. Don't take it to Mazda.

 

any mods??.,..is there any timing altering device on the car???

 

Did you ever hear any noise from the turbos, metal on metal? It's not normal since I've had my FD for almost 10 years and it's never done that. Even after driving it hard, you can barely see the glow on my set.

What ecu do you have? is the air pump disconnected or did you just remover the main cat but left the pump on it?

Tim

 

no mods, other than the downpipe that was just put on....origianl engine and turbos, 55,000 miles....don't know why it is idling at 2,000...believe it could be back pressure from the turbos...all idle screws are backed off...even disconnected ISC connector...I've pm'd BiState already

 

Call them but realize that isn't Thanksgiving and there will probably be no one there until Monday. I repeat and can't emphasize this enough, DON'T take your car to Mazda in St. Louis.

 

guys thanks for the replies

Tim it's the stock ecu...after putting on the dp and noticed turbo and dp were still glowing, I disconnected the main cat (separated the dp and main cat..the gap between them is about the length of the studs on the main cat) the airpump is still connected

 

bty my hearing isn't too good...so I really can't hear any metallic grinding

 

i believe if you find the cause ,why its idling at 2000 rpms you will cure the glowing,is anything messing with youre throttle/cable ??,that is kind odd

 

also check maybe for open manifold ,any disconected vacuum hoses like brake booster and such

 

thanks for the reply...I have checked the throttle cable as well as the cruise...also checked for vacuum leaks by spraying carb cleaner on all visible vacuum lines and gaskets

 

is nothing obstructing the throttle blades ,so they cant close ??,idling that high is most likely air sneaking itself in somewhere ,can you hear a vacuum leak ???

 

Felix,

I haven't checked to see if the throttle is completely closed...I have tried to push the thottle closed via the linkage...but as you imply, they (the blades,plates) may not be completely closed....I will pull the elbow later on today to verify that they are fully seated...don't hear any vacuum leak..but my hearing is bad..hence that is why I tested for vacuum leaks using the spray method

thanks again

 

good luck man

 

thanks again

 

man that is an insane problem. glowing at idle???? and a 2k idle at that , wow! hope it all gets fixed for you.
GL

 

heres something to think about books. There are 7 possible ways for ur idle to be affected:
ISC solenoid
AWS solenoid
ACV solenoid
fast idle screw
Screw on the bottom of the TB (forgot its name)
vac. leak
stuck throttle cable.

If any of those soleniods are faulty, they can become "stuck" so to speak, and wont close even after you disconnect them. That was my experience with a high idle anyway. Also, turn on your lights and/or a/c. If the idle raises about 500rpms and bounces between a range (1500-2000 for instance), then its an electrical problem.

-Zach

 

thanks Zach,
you have a pretty good approach...as I recall the ACV could be stuck and not set a memorized code...fortunately, I have spares for a couple of those solenoids thanks to Justin Huegel

 

when my quad used to run really lean my exaust pipe would glow, i could put **** to it and it'd light on fire

 

ok........that was informative ....got ****?....wtf!

 

here's an update: just pulled off the throttle body elbow, the butterfly valves (plates) are seated completely...turned on a/c and lights and the idle dropped to 1,400- 1,500 rpms...the idle was pretty darn steady no oscillating..it did gradually increase to about 1900 rpms but dropped back to around 1,400 rpms...again the primary turbo area was glowing as well as the downpipe

without an electrical load the idle is still around 2,000

do you guys think that fixing the idle problem will eliminate the glowing turbo and downpipe

 

yes i defenetly think it will ,..have you checked see if youre throttle position sensor is moving (loose) , i dont think that it will be the cause of that high idle ,..but it wouldn`t hurt to look ,also have you checked the iac valve already ,..if everything is closed ,even the air adjustment screw (under throttle body) then air must be entering from some where ,...just to be safe is youre brake booster working ,...if the booster is leaking it could be a problem also

 

Okay, when did the 2krpm idle START?

 

Is your DP stainless or mild steel? Obviously you need to find the cause of the high idle, but I still find it alarming that your turbo and DP begin glowing shortly after startup? How long does it actually take for the turbo/DP to begin glowing? It takes at least a few dips into boost for my turbos to even show a hint of glowing, and yet both your primary turbo and DP glow from idling, even at 2000 rpm? Not to confuse things even more, but I think you've got additional issues besides the high idle.