coop

Hello all,
I have a problem.
I just installed a DP today. I got it used from a guy, he told me it was Bonez (if that makes a difference)
First, here is how the install went:
I removed the BOV hoses so I could get to the top part of the DP. I also removed the Intercooler hose that goes over the air pump. I also removed one of the big hoses from the intakes to the turbo.
Two studs came out with the nuts. one didn't. The third was just a bolt (someone must have put that in there, it came with the car when I got it). I didn't replace any gaskets. The DP -> CAT one looks like it needs replacing but I forgot to get one and I wasn't at a place where I had another mode of transportation. The Turbo -> DP gasket looked ok.
I thermal wrapped the DP. Put the DP in...first MAJOR problem.... I got three of the studs (actually 2 studs and the bolt) back in. The forth one, the one that you can't see, (on the top of the DP) didn't seem to line up.
So it isn't in. (I know this is very ill advised). But I had to leave my house. I tightened the three I had in as much as possible (without stripping them). I am wondering if I have a exhaust leak at this point.
Next major problem. The sensor (That is the O2 sensor right?)...well I unpluged it, and then while removing the DP the wire snagged on something and pulled the wire out of the sensor. (I wasn't happy). So I crammed the wire back into the sensor. (Ill advised I know). So this sensor is in the DP.
.
I turned on the car and prayed. It started fine, but there is a loud rumbling/grrrrrrring coming from the engine comparment where the DP is. Is this because the DP lets more sound though, or because I have a leak?
I couldn't See exhaust coming from around the DP & turbo junction, but that doesn't convience me...
When driving the car I get practically 0 boost. I can hear the turbos now, but they didn't give me any umph. I didn't drive the car hard at all, but just starting from a stop had a noticable drop in power.
HELP!

Should I take the DP off and try to bore out the hole I can't get lined up? Should I put the old pre-cat back on? Should I get new bolts for the DP?

I tried to search the 3rd gen list for DP problems, but Ididn't see anything like this, if I just missed it you can post the link...

Thanks a bunch for any help/ suggestions you can offer
-Dave

pweizman

Well, first off, you need to get the fourth bolt in the Downpipe. Just keep trying to get it lined up, and thread it in. Examine the threads, and make sure they are not bunged up. If they are, go buy a new stud or bolt. Once you get it started in the hole, I would loosen the other three a bit, and re-tighten them all together to make sure you have an even seal.

Next, I am confused....did you hook the O2 sensor back up? If you just shoved the wire back in the harness, chances are it is not working right. Either splice the wires back together, or go get a new O2 sensor.

I wouldn't drive the car in this state either. Fix it first.

If you can't get the bolt in, take it to a rotary mechanic, or a muffler shop....

Hope that helps.

Later,
Patrick

coop

I would have spliced the wire together, but it pulled totally out of the sensor, it didn't just get cut.
I will definitly get a new one...can I get it at a local car shop or is it a special order?

Anyone know about the sound? is it from missing the bolt?
-Dave

afterburner

Sounds like you had one hell of a time. Get that 4th nut in and get a new turbo-downpipe gasket or you can try silicone gasket maker with your old one. Get a new O2 sensor (Bosch universaL) if the stock one is fucked. If the wire was just cut, solder them back together or use metal wire connectors. Boost problems, will be most likely due to improperly installed hoses, so double check those.

coop

Ok, I got it all figured out...
low boost = intercooler hose fell off...must have forgot to tighten the hose clamp (stupid)
Exhaust leak (definitly) = well when putting the DP back on the gasket must have got mis-aligned. so when I tried to put the bolts in only 3 would go in, (the fourth hit the gasket). So there was a major leak.
I couldn't get the gasket ligned up so I used a little dot of high temp engine glue from when I put together my VW Beetle to hold the gasket on. Then I didn't have to worry too much about the gasket coming off.
I could then get all 4 bolts in.
I ordered the dp->turbo gasket from the mazda dealer....$41.50...arrg.
So some weekend I will take it all apart and put the new gasket in
QUESTION:
Should I use both gaskets...old + new. or just the new one when I replace it?
I also replaced the O2 sensor...with a Bosch Universal...it was $18 opposed to the $100+ for the OEM sensor.
I also took this oppertunity to put a heat shield in for my APexi intakes! So it was a much better night.
The car runs much better. I missed it so much!
THanks for suggestions and tips!
-Dave