jantore

Im having a veird problem with my car. The thing is, i was at the track 2 weeks ago and during a acceleration in second gear the car started to stutter and would not accelerate. When trying the car would stutter and my boost gauge would jump upp and down, not wanting to go over 0.3 bar.

I had the same problem before, then it was a plug that had fallen out, that i had put in where the air pump should go. But this time it was still there.

When i got home i stoped the car, poped the hood and started the car again. Then i could see exhaust smoke coming upp between/around the turboes. I tracked it down yesterday to be the hole coming out frome the UIM, where the pipe going to the cat should be. I removed it, and did not block it off. So i blocked it off.

Then i went for a drive, and i could boost all the way, but the needle on the turbo presure gauge still shakes when accelerating. And now i have a weird sound. Like a fast bap bap bap/brrrrrrrrrrrr sound. It sounds strange. This is only when i get boost presure. Not if i rev the car without eny presure.

I have checked the map sensor, and also checked the compresion and it's good. Vacum when car is idling is about 0.59 kg/490 mm/hg. So i don't think it's the engine. And it's just rebuilt. Only run about 3500 miles. Using the new mazda 2 piece 2mm seals.

Eny clues would be great. Il try and get some sound of it tomorrow.

jantore

Oh and one more thing, the car do not pull as strong as it used to do.

jantore

hmm nobody knows eny thing.

is there noone that have had this problem?

skunks

try to post a sound clip or some video of it. as of right now, i dont got a clue on what it could be according to the sound. oh, do you got any pics of this mod you did, "I had the same problem before, then it was a plug that had fallen out, that i had put in where the air pump should go. But this time it was still there." i dont understand what you did.

SWAT81

iTrader: (14)

Sounds like turbo rebuild time to me, my pull isn't as strong as it used to and its not 100% stable either. Perhaps I have a leak somewhere

jantore

skunks, what i mean is that i removed the air pump and blocked the line that was going to the airpump, and that other line coming of the UIM that goes to the air filters. One of the plugs that i put did fall out under a track session in september, and then i did get the same sympomps.

But i forgott to block of the hole, where the pipe frome the airpump coming out frome the UIM. Where it goes down to the cat. Now that i have blocked it off, it did get better, but not good.

Il try and get a movie out later today, with the sound.

jantore

Her's a short clip of the car with the engine running, and a compression test on both rotors.

http://www.bilforumet.net/video/bil.avi

It's 10 mb.

Here that strange sound, when the car drives by, and idles later.

jantore

Here's another link on a faster server.

http://mm3.raboc.org/~olekvi/mm/jantore/bil.avi

kundo

Are you still running a cat or do you have a midpipe? Maybe you got a clogged cat. I didn' watch the videos 'cuse Im on Dial up so it takes to long.

jantore

maybe i should list my mods.

Modified full exhaust, DP, MP, catback
FMIC
HKS air filters
Upgraded ECU
Boost Controller @ 1 bar
removed air pump

FDjunkie

I recently lost some power due to a boost leak (a intake hose in my case) that was small enough that the turbos could overcome it and therefore still produce full boost pressure, it just took longer to reach that level. In my case there was also some unusual noise whenever I boosted over 5-6 PSI, so I could rev the engine while parked and not hear the noise.

I tried listened to your sound clip, but couldn't tell much. Maybe too much is lost through recording & processing.

jantore

FDjunkie yeah the sound is not so good, nut if u use a head sett it's much better.

The thing is tha car studders, and the needle on the boost gauge jumps alittel bit upp and down when accelerating with boost presure. And that is a symptome of a blown apex. But could the studdering of the car and the boost gauge come of a turbo that is dieing?

FDjunkie

When I had my problem the boost gauge needle didn't do anything unusual; just didn't rise as quickly as normal. Guess that points more to some other kind of failure.

Compression test should confirm status of apex seals. If they are all ok them maybe something failing in the wastegate/bypass/charge control system(s). I guess one or more of these could produce some strange noise, along with a loss of power and fluctuating boost gauge needle.

jantore

compression reads atleast 120 psi on both rotors, so that's ok. But it's that strange sound, and that the needle acts like a blow apex.

jantore

Ok, i found my problem. It's the F&%¤&#¤&#&ing spark plugs. They are dead after only 4000km (6400 miles).

The car ha run about 1000km (1600 miles) of that on a race track.

So solved problem by cleaning them, but do need new ones. Will get next year when im finnished with the car.

911GT2

Glad to know you found the problem. Your car is beautiful by the way. I love the sleek headlights.

jantore

thanks, i love the headlights my self.

I have now parked the car for the winter, and will start my singel turbo conversion pretty soon. And i will also repaint the entire car, even inside the engine room and the trunk.

It's going to be a fast race car when it's finished. With about 500 rwhp.