PunjabiM3

Hey folks just purchased a 993 Turbo from a PCA member from out of state. Flew out to look at the car a few weeks ago and also had a PPI and compression test done by the local P-car dealer. Car is in great shape, drove great when I went to check it out, though admittedly I did not go WOT for any length of time while testing the car out. The previous owner has been a pleasure from the first call I made to even now post transaction.

The car arrived this week as I had it shipped via Passport Transport. Took it out for a spin and drove real nice, though I noticed when I got on it it would not show more than 0.5 bar of boost on the built in display. After about driving it 30 miles, when pulling into my neighborhood, I went WOT in 1st gear and into second...and the car just sort of stalled and died. It started right back up, only to die again within seconds. I popped the engine compartment and after poking around, noticed that the hose coming off the right side of the intercooler had popped off. After haggling with it for a bit, I was able to get it back on, but after attempting to tighten the hose clamp, I came to the conclusion that the clamp strips after tightening for a bit. In any case, I was able to start up the car and drive it no problem into the garage. I have since replaced the clamp and the car runs fine; however, it still is not boosting past 0.5 bar. I have spoken with the previous owner a few times and he is also surprised as he said the car always boosted to 0.8 bar (pre compression test and PPI). We are both thinking that perhaps the P-car dealership did not fully tighten some of the other hoses? I am wanting to check all the hoses that may have been taken off when the compression test was done, but not sure which ones to check and how to best access them? Any input would be greatly appreciated as to what to check and what else can be causing the car to only boost to 0.5 bar. The previous owner has also told me I can take it to a local P-car dealership and he will pay to have the problem fixed. Your help is much appreciated in helping to diagnose and fix this issue. I live in the Dallas area if it matters. Thanks!

chsu74

1. Digital boost gauge is not accurate.

2. Get breeze clamps from Amazon for your hoses. Do a search here as it has been discussed in detail.

rlme36

^^ what chao said and get the upgraded boost hoses if the ends show any sign of rips or tears.

Dick in TN

I also have breeze clamps and haven't blown a hose since. I also replaced my hoses with new factory hoses at that time because the ends were splitting.
My boost gauge shows .8 bar, like it always has the twenty years I've owned my car. Get that checked, yours should too.

ctsang103

I had a similar problem that required changing out the N75 frequency valve. Good luck!

OverBoosted28

If you're blowing any hoses, assume all hoses MAY be suspect. Go through and replace the 5 hoses, that are under direct boost in the system. The ports at rear, of das of intake, are tiny brass nipples. Those hose ends get cracked, loose and slip off regularly. This is where I think you're losing some of your boost. Eliminate those possibilities, and then you can try and see if a leak is the issue.
Note: I have always used rubbing alcohol to clean, and lube the hoses/areas where they mate. The alcohol will lube the silicon, then evaporate, and you should get a good purchase. Some use hairspray, as a slight adhesive inside hose ends. Good hoses/good clamps (t-bolt), and you should be fine.

Mike J

BTW, I would avoid full throttle in 1st - the engine has enough power to possibly twist the main-shaft of the transmission.

Cheers,

Mike

PunjabiM3

Thanks for the feedback guys! The car otherwise runs great aside from it only showing 0.5 bar boost. I did order the breeze clamps for piece of mind.

Another question: what impact does heat and humidity have on these air cooled turbo motors, specifically boost levels? I live in Texas and since I took delivery of the car 10 days ago, it has pretty much been around 95-100 degrees with heat indices of 100-110. Is it also possible that the car only boosts to 0.5 bar due to the very hot temps and high humidity? This is something I have wondered since day one.

Dick in TN

The temperature and humidity is not the cause of your car not reaching it's designed boost level, or if it is, your gauge not indicating this.

dbf73

have you tried checking the boost in 3rd or 4th gear?

PunjabiM3

Thanks for the feedback folks. I did order the clamps and changed out the top end ones that attach to the intercooler, but still having the boost issues. I suppose the next step would be to check the lower connections. So what is the best way to have visual access to these connections and also to reach them if they are indeed loose or not on straight? It is so hot here in Texas (and we just had a baby girl this week) that I am just thinking about taking it to the dealer. Trying to figure out whether better to take it to local Porsche dealer or RAC Performance to have it diagnosed and fixed, as I just don't have much time currently to mess around with it (unless it is fairly easy to access everything).

Fred Wagner

PunjabiM3: I have been thru this with the two 1996 993TT's I've owned. The dash boost gauge is crap. I installed an external boost gauge on the "A" column. I removed it when I bought my Cayman and it can be yours for $75.00. Email me if interested at fawagner@***.net and I'll send photos. The breeze clamps and 'orange' hoses were a must. Regards, Fred

PunjabiM3

Had a chance today to drive the car some more. Weather was around 7-10 degrees cooler outside with 10-15% lower humidity. Drove her to my doctor's appointment; at first it was much the same...0.4 to 0.5 bar boost on the way to the office. Then on the way home I made a few pulls in second and third gear, and to my surprise the gauge is now indicating 0.8 bar boost. Came home, did a few errands, and then drove her to the grocery store, car again indicating 0.8 car boost! She feels quicker than before, and for now am happy just to see the gauge showing the 0.8 bar! Next question: after coming home I did notice a bit of oil running down the left intercooler hose. The hoses I have are all black and not the updated ones with the orange ends (as far as I can tell). Also, when the right side hose popped off a few weeks ago, I did notice it had an oily residue on the inside. I assume this is normal? Good idea to replace all of the intercooler and turbo hoses/piping with new upgraded ones for preventative measure? I am also planning on putting on an exhaust, so guessing when that is done it would be a good time to get hoses replaced while that work is being done. For exhaust I am thinking of getting the Fabspeed X-pipe with high flow cats in conjunction with either their supercup exhaust or Fister mufflers. Feedback much appreciated!

chsu74

Mods:
1. Replace cats with Fabspeed or FVD 200 cell.
2. Muffler - Fister or Fabspeed bypass. Fister is not as "barky" and both sounds great.
3. Update shifter with Golden Rod from FD Motorsports.
4. You can replace clock with a analogue boost gauge like below by sending it to WSM in Germany. I have spare clocks if you want to keep your stock clock.

Enjoy the car. Nothing else is really needed.

nine45s

Punjabim3,

Oil running down the intercooler hose is not normal.
Read the sticky at the top of the forum.