Sudden Loss of Power
02-27-2006, 07:32 AM
#1
Advanced
Thread Starter
Join Date: Feb 2006
Location: Germany
Posts: 57
Likes: 0
Received 0 Likes
on
0 Posts
Sudden Loss of Power
Hi Guys, I'm new to this forum but having looked through quite a few of the threads it's clear that there are some serious experts among you. I am quite the opposite and here to learn, so I thought I'd drop my 'bomb' and see what response I get -
Any takers?!
I purchased a 930 out of second hand (I am third) beginning of November 2005 with 114000km (ca. 70k miles), it's a moss green metallic turbo with a production/factory upgraded engine to 330bhp/243kw, (like the slantnose rating I think), I should add of course that it's an '86 930. Shortly before Christmas the car lost all power whilst driving, it had been suitably warmed up to running temperature and as I pulled off of a slip road onto the Autobahn (I live in Germany) I put my foot down (in 2nd), nothing too drastic (my eyeballs were still in my head) and shifted up into 3rd, as I needed to turn off at the next sliproad I eased off the gas and as I put my foot back down gently again, when I noticed, oops no power, the engine was still ticking over with the rev counter gradually falling, but I had to pull over and eventually switch off once the engine had idled all the way down, I basically rolled to a stop. There was no oil leaving, or any kind of fluids visible. Two minutes later I fired it up again and it was fine, crept home at under 3000 revs though. Anyone got any thoughts as to what it could be due to? Suggestions have been fuel filter, fuel pump, fuel line? One suggestion is that due to it being a factory upgrade the engine is sucking so much fuel that if over time the pressure has reduced in the fuel pump/fuel pressure regulator that might have had an effect. But I had taken it out for a couple of hard runs (since buying it in Nov 05) before that without problem. Help is appreciated! Thanks
Any takers?!
I purchased a 930 out of second hand (I am third) beginning of November 2005 with 114000km (ca. 70k miles), it's a moss green metallic turbo with a production/factory upgraded engine to 330bhp/243kw, (like the slantnose rating I think), I should add of course that it's an '86 930. Shortly before Christmas the car lost all power whilst driving, it had been suitably warmed up to running temperature and as I pulled off of a slip road onto the Autobahn (I live in Germany) I put my foot down (in 2nd), nothing too drastic (my eyeballs were still in my head) and shifted up into 3rd, as I needed to turn off at the next sliproad I eased off the gas and as I put my foot back down gently again, when I noticed, oops no power, the engine was still ticking over with the rev counter gradually falling, but I had to pull over and eventually switch off once the engine had idled all the way down, I basically rolled to a stop. There was no oil leaving, or any kind of fluids visible. Two minutes later I fired it up again and it was fine, crept home at under 3000 revs though. Anyone got any thoughts as to what it could be due to? Suggestions have been fuel filter, fuel pump, fuel line? One suggestion is that due to it being a factory upgrade the engine is sucking so much fuel that if over time the pressure has reduced in the fuel pump/fuel pressure regulator that might have had an effect. But I had taken it out for a couple of hard runs (since buying it in Nov 05) before that without problem. Help is appreciated! Thanks
Last edited by Dickyboy; 02-27-2006 at 10:37 AM.
02-27-2006, 12:52 PM
#2
Rennlist Member
Dickyboy (ahem..interesting name) - Before suspecting fuel and all that other good stuff...do a THROUGH inspection of all your hoses and connections from the turbo through the intercooler and into the throttle body...a slight leak or bad O-ring will cause boost to **** out faster than a horse on steroids - hence lack of powa!
Failing that do a compression and leak down test on the motor to measure engine health. Good Compression umber will be more than 120psi and good leakdown nmber will be less than 10% this is on a wrm or hot engine!
Then you can start looking at your fuel system and your turbo.
Seeing as you are in Germany, you should be able to locate some VERY competant mechanics to toruble shoot the car.
Hope that helps - Yasin
Failing that do a compression and leak down test on the motor to measure engine health. Good Compression umber will be more than 120psi and good leakdown nmber will be less than 10% this is on a wrm or hot engine!
Then you can start looking at your fuel system and your turbo.
Seeing as you are in Germany, you should be able to locate some VERY competant mechanics to toruble shoot the car.
Hope that helps - Yasin
02-27-2006, 03:44 PM
#3
Race Car
Join Date: Sep 2005
Location: England UK
Posts: 3,508
Likes: 0
Received 0 Likes
on
0 Posts
One other thing you could check is that the "safety overboost switch" did not cut in for some reason maybe it is faulty or maybe you overboosted for some other reason.
I think this switch screws into the intercooler and has 1 wire going to it. It is the smaller device (the larger one with 2 wires is the sender for the boost gauge in the rev counter).
To bypass it just connect the single wire to a good earth. When testing make sure you don't overboost the car, watch the gauge and be careful with your right foot. I have an additional boost gauge in my ebc so I know how much boost my engine is getting after the intercooler. Overboosting your car will melt the engine so make sure you don't go over 1 bar of boost.
Only one pipe is connected on the wastegate (the bottom one), the top pipe is vented to the atmosphere in the engine compartment. Make sure you bottom pipe is connected to the intercooler and nothing is blocking the top one.
Good luck and let us know how you get on.
Sounds like you have an interesting car, add your location to your profile so we know where you car is from, most people on here have USA versions of Porsche's which are different.
I think this switch screws into the intercooler and has 1 wire going to it. It is the smaller device (the larger one with 2 wires is the sender for the boost gauge in the rev counter).
To bypass it just connect the single wire to a good earth. When testing make sure you don't overboost the car, watch the gauge and be careful with your right foot. I have an additional boost gauge in my ebc so I know how much boost my engine is getting after the intercooler. Overboosting your car will melt the engine so make sure you don't go over 1 bar of boost.
Only one pipe is connected on the wastegate (the bottom one), the top pipe is vented to the atmosphere in the engine compartment. Make sure you bottom pipe is connected to the intercooler and nothing is blocking the top one.
Good luck and let us know how you get on.
Sounds like you have an interesting car, add your location to your profile so we know where you car is from, most people on here have USA versions of Porsche's which are different.
02-27-2006, 06:56 PM
#4
Advanced
Thread Starter
Join Date: Feb 2006
Location: Germany
Posts: 57
Likes: 0
Received 0 Likes
on
0 Posts
Hi guys, thanks very much for the help, good comedy value too! You're right I should be able to find someone on my doorstep over here who's competent enough! I'll have it checked out soon as and report back!
p.s. The sign on is a name that's just stuck, it's merely a reference to Richard (my forename)!!! :-)
p.s. The sign on is a name that's just stuck, it's merely a reference to Richard (my forename)!!! :-)
03-03-2006, 05:19 PM
#5
Three Wheelin'
Join Date: Aug 2005
Posts: 1,980
Likes: 0
Received 0 Likes
on
0 Posts
In addition to all of the good advice above, check all of the fuze and relay connections and grounds on the fuel pump circuits. I had a bad fuze take me off line in the middle of nowhere Pennsylvania. A 100 mile tow to Harrisburg and the local Porsche dealer and boy was my face red when it turned out the previous owner must've put a slow-blo glass fuze in the box (of the proper rating) but those things get so hot it spalled molten solder inside the glass. When a solder ball would lodge itself just the right way in the car it would short down the pumps and the car was dead. The ***** were so small I didn't see them (the fuze still looked good) but it just didn't click with me that we shouldn't of had that type fuze in the box.
