Went over to Surrey rolling road today and it looks like my car may have a small problem. Boost is not as high as it should be (1.2bar vs 1.35bar) and coming later than in should (max not till 4300), and fuelling is waaaaay too rich.

It could point to boost leak, which may fit with the fact that I installed an charge temp gauge yesterday and put it through the hose connecting the intercooler and the throttle body. I've checked all the connections and they seem tight and the fact it is a little below peak and dropping over the rev range may suggest not a major, just a minor leak.

Graphs are below (and I've sent them on to Zak at Mocom who has been doing the mods to my car and mapping as I'll be taking it to him to sort out!). Car is a 2003 WRX with 550cc pink injectors, VF34 turbo, PPP kit and prodrive sports cat downpipe.

Bugger! Luckily I did keep the old connecting hose and buy a new one to fit the gauge sensor to so I can always go back in the interim...

 

Did you know it wasn't right ?
Can you feel something's wrong when driving ?
If so cant you just swap the interconnecting hose and see if it changes anything

 

Agreed put the old hose back on and see if that solves the problem.

 

How have you mounted the temp sensor into the hole - with a boss or just poked through a hole in the hose?
I use a thick wire gauge K probe and put a dab of superglue over a very tight hose hole.

If the IC has been disturbed then it may be the hose out of the turbo isn't seated.
Any new whistling or rasping noises when spooling the turbo up?
An up-pipe leak also springs to mind.

nick

 

I have the charge temp. probe in the silicon hose as per yours but with no problems. I made a hole in the hose and screwed the boss in and sealed with silicon then wrapped over and around the boss with special silicon tape, available from Viper Performance, going inside the hose as well. Obviously, all this was done with the intercooler and hose removed.

JohnD

 

I used the brass two part fitting that came with it (one bit outside, one inside and then screw together through the hole), but didnt use much silicone sealer. Have now doused it in the stuff in the hope that it may help!

No noises (whooshing or whistling)that I can hear, but the old flat four burble when on boost does drown most things out!

 

Took the car to Brands Hatch today - it's not something that I noticed on the road, but its definitely slower than usual on the track.

I took a good look last night and reseated everything and silicon sealed it to death and its still not holding boost (though max boost at times on the track was 1.3bar). I douth that it could just be the sensor now as nothing is getting through the ugly mess of sealer on it!

Looks like a trip to get it sorted by someone who knows what they're doing!

 

I think your right could be something else coursing your boost problems good luck tho mate

 

what fuel pumps do they models use. do they max out at 280bhp. anybody think if he used a walbro he would be looking in the regions of 300+bhp?

 

I didn't pick up on the AFR. I'd start with making sure the intercooler hoses have been put back on properly.
Was the car mapped recently?

 

Yes the car was mapped a couple of months ago when I had a sports cat and upgraded injectors fitted. Also had a walboro fuel pump fitted as the oem one couldn't keep up.

I've checked the hoses and they look properly fitted and are connected tight. The overfuelling on the plot would suggest the engine is expecting more boost but it's not getting it?