Hi,
I have a question regarding my turbo. The exhaust-pipe glows red even after just running warm in idle. I don't think that's normal. Any idea, what the Problem can be?

 

Some things you might want to check. The Oxygen Sensor, timing, having the correct injector sizing, AFM, clogged catalytic converters,good condition spark plugs, working ACV-air pump.

 

The engine gives no error-code at the moment and the spark-plugs are new.

I will check the timing the next days.

How do I test the oxygen sensor and the air pump? And what is AFM?

 

Take the dp off, start it and see if it still glows

 

Remove the hose that connects to the air pump at either end of the hose and w/the engine running it should have air rushing out of it (the pump or the hose end).

The AFM is the Air Flow Meter. If the flapper door opens too much it will enable the ECU to inject more fuel than required and too much fuel leads to the excess fuel being burned in the exhaust manifold which causes a higher than normal temperature thus a glowing exhaust.

The FSM shows how to test the Oyxgen Sensor along with numerous writeups on this site which can be found by engaging in something called "the advanced search."

 

number 1 question is do you have leading spark , pull off the lead and test for spark
without it the engine will burn 15 degrees late , and the glowing pipe is typical of that

number 2 question is the set couple left bridged? this will lock the timing at idle timing,, another good reason the pipe and cats will glow

 

Can you clarify what you mean by that, exactly?

 

it's a yellow 2 pin connector on the passenger side strut tower. it's stated in the FSM as the "initial set coupler".

 

The Spark was there on all plugs the last time I checked. But I will test it again.

I havn't left it bridged. Neither with the "debug"-pin (driver-side for Error-Code-Reading) nor with the yellow connector which i believe is for the fuel pump.


Just to clarify, I have a S5 turbo. It starts fine cold and hot and runs with a smooth idle at around 800. Only Problem is that after a cold start, i have to stay a little on the gas 1 or 2 minutes, or the engine will die. Propably a Thermowax issue, which I havn't fixed yet.

 

that's the fuel pump test connector. the initial set coupler is right next to the leading coil behind the driver side headlight.

 

I'd guess failing catalytic converter.

 

that look HOT!!!

 

nice!! is that on idle or after a good run ? i say very lean or timing/ignition issue

 

I had this problem before. My issue was being confused by using an S4 crank pulley on an S5 engine with an S5 front cover. I don't remember the exact details, but I know it's pretty hard to set the timing unless you have all the parts matched correctly. And I remember it being a little difficult to find the actual, real TDC. I think there is a thread that shows how to find TDC accurately using 'fluid displacement', a lot of trouble if you ask me, but you gotta do right. Definitely could be something other than the timing though, good luck and fix it quick before you burn out that turbo.

 

I was under the assumption they're all interchangeable....

 

^NO. Mazda really "screwed up" with the pulleys. That pulley was really only made for that hub. Sure it may work on another car, but it might not. It's been known to be off between different pulley/hub combos and also between series.

 

I will take out the timing gun if I have time under the week. The plan for the weekend is to take out the precat and clean it out.


Does anyone know, if the S4 Turbo Downpipe fits on the S5? I could get one of these...

 

yes, dump pipes interchange

 

thats why you install the pulleys on the eshaft(out of the engine) during a rebuild and check the "trueness" of the timing marks ;D

 

Okay, today I pulled out the cat after the turbo. It rattles a lot, if you shake it. So I tried to clean it out, but I can't get the filling out, cause of the curve the connection Pipes make. Is there any trick to do it?

 

take a metal pipe and pound it apart.

 

i had the same problem. it was timing for me, once i fixed that no more glowing.

 

I havn't timed it yet, as I first wanted to take out the converter, but can it even be bad timing? I mean for temperature this high it has to run very lean or much to fat. But if it is either side, would the car even start? And my one runs a perfectly fine idle, whitch isn't what you expect from wrong settings...

 

I'm searching for a matching downpipe at the moment.

Thanks for all the tips, I will check the sensors and the timing the moment, I can safly start my car again.

 

clogged precat