purchasing 928s

12magnum · 12-15-2005, 01:33 PM

hey guys I'm new to this group. I am looking to buy a porsche 928s. I have looked at a 1986 model that appears to be in outstanding condition, glossy paint 65k miles clean interior. car has all documentation and I ran a carfax check that came up clean. (hopefully this guy needs the money for christmas) It is snowy here, so i haven't driven the car but we did start the car in the garage and ran it for about 10 minutes. I am about to make an offer on the car pending a test drive and a Pre purchase inspection. My question is what is the engine/injection system is supposed to sound like. I could hear a very faint "ticking" sound. do the injectors make a little noise when they fire? I just want to make sure i'm not hearing valves. maybe someone could even take their PDA out to the garage, lift the hood and start the car, making me a wav file to compare it to. thanks in advance

jstobo · 12-15-2005, 04:33 PM

The electronic injectors do make a clicking sound but I do not think you can hear them from inside the car. Hood up and ear close maybe. The engine has hydraulic lifters so there is no valve adjustment. But if a lifter isn't staying full of oil it could cause a tapping sound. Hope this helps.

Rixter · 12-15-2005, 05:19 PM

as noted above, lifters are a common suspect for the tapping sound
if you are considering a 928 purchase it is HIGHLY recommended that you get a PrePurchase Inspection (PPI) by a 928 mechanic PRIOR to getting the car
the 928 is one of the most incredible cars you can drive, unfortunately many are neglected and the little things can add up quick, a $5k purchase can become a $10k money pit in no time

12magnum · 12-15-2005, 05:39 PM

i should clarify The clicking or ticking noise is very faint, and i could only hear it with the hood up. it cannot be heard inside the car. other vw's or audi's i have owned of mid 80's vintage had the Bosch CIS which does not make any noise. I would agree that a car with hydraulic lifters should have zero lifter noise.

928ram · 12-16-2005, 04:34 AM

Sounds like injector noise. Usually lifter noise is somewhat loud and fades with warmup. I'd say it's normal as I've heard other 928 owners state that they can hear their injectors with the hood up.

Good luck with the purchase (if all checks out); looking at an '86 if the VIN's last 4 digits are above 999 it'll be equipped with the S4 style suspension, brakes, exhaust which is a bonus.

12magnum · 01-03-2006, 08:21 PM

guys, thanks for your replies. since i drove this car i went and drove another 32v 928, and the engine sounded identical.

..P · 01-05-2006, 10:45 AM

It does sound like injector noise, but it also sounds like the normal sounds of a double overhead cam engine with 4-valves per cylinder. There are a LOT of moving parts, and hearing a faint ticking noise is probably the sound of a healthy engine.

I agree that most of the ticking is probably coming from the injectors. In order to isolate the "tempo" and the actual frequency of this noise you're hearing, you could take a long handle screw driver, and put your thumb over the end of the handle, and put your ear to your thumb. Then probe around near the injector, you should be able to understand exactly what an injector sounds like. Better yet, get a mechanics stethascope. If you use the screw driver technique, take all due precaution to stay out of the rotating machinery, including the electric aux fan, and stay away from the high tension wires.

My main concern would be evidence that the timing belt had been changed within recent months and milage.

regars, P

12magnum · 01-05-2006, 08:49 PM

thanks for the reply. the engine noise is a non issue, i'm sure there's no problem.

the timing belt was changed 17,000 miles ago, along with rollers. but that was in 1996 so i'm thinking the belt should be changed. a new belt is not expensive. the water pump was changed in 1992, it now has 31,000 miles on the pump. i might change that too while i'm at it . any opinions on this?

Rixter · 01-06-2006, 04:48 AM

the tb/wp MUST be changed!
as a rule 4yrs/40k miles whichever comes 1st, ALWAYS change BOTH at the same time, plan on $400 in parts and 12-15 hrs time to do the whole job including rebuilding tensioner

12magnum · 01-06-2006, 08:45 AM

Rixter thanks for the reply. any suggestions on which belt to use. Continental or porsche belt? porsche belt is over twice as expensive. pump- obviously a porsche pump is probably best but cost is 565 bucks just for the pump. a new Laso pump is $281. rebuilt pumps cost in the $120 range. I was thinking about buying a kit with everything (rebuilt pump, belt tensioner rebuild kit, gaskets, tensioner roller, idler roller, tensioner bushings, kempf tool, flywheel lock tool)

Rixter · 01-06-2006, 09:25 AM

call 928Specialists 828-766-9280
they carry a "kit" for this that you can add/delete whichever options you want
continental belt is perfectly fine, it's what I use..
where are you located? there may be a 928 owner near you that would be willing to lend you the kempf and flywheel lock tools

12magnum · 01-06-2006, 10:06 AM

i am in washington state

Rixter · 01-06-2006, 12:34 PM

plenty of 928ers up your way, check out Rennlist you're sure to find someone near you to lend some advice and possibly help

928ram · 01-06-2006, 07:38 PM

Check out "Yahoo groups" for the local bunch of 928ers ( I think it's PacNW928 at yahoo groups); they have a seperate mail BBS and are a very active bunch that includes WA, OR, ID, and SW Canada members. Great bunch of guys.