cold_beer839

I'm looking at a '93 GTS.

I need some info from you guys.

1. What is the difference between early and late vin '93s?

2. Oil consumption, is it a problem with late vin '93s?

3. What things should I definitely inspect closely during a PPI on a '93 GTS?

pcar928fan

Be sure the PSD is working... wet pavement is really good for that...

Be sure the cruise is working.

No leaks.

Check the tire pressure monitor be sure that will work correctly... Unless the tires have about 38 psi in them it will probably come on and tell you they are low...I would then pump them up and be sure it does not fault on you again...

ALL GTS's use a bunch of oil... There are esoteric engine differences between the 92/early '93 cars and the later cars... I don't remember what it is though. I think Erkka (did I even get close to spelling that right) is the master and knows all this stuff...

Otherwise just look at all the regular stuff.

Vilhuer

> 1. What is the difference between early and late vin '93s?

Besides obvious VIN difference not that much. Early '93 US cars are basically '92 MY model made in early part of '92 calendar year. There are few engine part differences between them and later cars.

- Early '93 (= ROW '92 MY) have studs in block lower half. Late '93 (= ROW '93 ROW) to end of '95 MY use bolts.
- Early '93 (= ROW '92 MY) use weaker pistons and have oil ring design which seem to more easily cause oil consumption. Late '93 (= ROW '93 ROW) to end of '95 MY use pistons which have strenghtened skirt and different design oil ring.
- Early '93 (= ROW '92 MY) use older S4/GT style breather setup in cylinder heads. Late '93 (= ROW '93 ROW) to end of '95 MY use slightly improved version which can be fairly easily retrofitted to earlier cars.
- Engines up to first hundreds of engines made at begining of '94 MY use weaker ...1R casting number connecting rods. Factory recommendation is that they are replaced with stronger ...2R rods whenever rod nuts are opened. I can't recall offhand exactly which was first engine from factory to receive ...2R rods but numbers are somewhere in archives. Same rod design change applies to 968 engines also.

Other than above there weren't many mechanical changes. '94 MY got pollen filter and dynamic kickdown but lost RDK at same time. This doesn't include first US model '94's as in reality they were made in spring '93 calendar year already and they are from technical point of view '93 MY cars.


> 2. Oil consumption, is it a problem with late vin '93s?

Less than in early cars but it can happen. There are some much later cars which received spare engine from factory under warranty and some engines were also rebuild by dealer to fix the problem. In some cases nothing Porsche did helped.


> 3. What things should I definitely inspect closely during a PPI on a '93 GTS?

Thrust bearing failure in case car has automatic gearbox.

PS. James, your spelling is fine.

cobalt

The RDK seams to only come on with a differential in tire pressures. So if they are all set low or high it doesn't seam to make a difference. I find if there is more than a 4 pound difference between my tires it will set off the RDK for the tire that is lowest.

The Boge shocks are more than likely shot check for dampening.

My cruise control is incredibly accurate set it at one speed and it does not vary more than 1mph under all conditions up and down hills. I have seen some work but will fluctuate by +/- 5-6 mph.

My late MY 93 has no issues with oil consumption but apparently that is not always the case. I would also check the coolant hoses as you are probably aware of.

Otherwise standard 928 stuff.

928ntslow

RDK is easily bypassed. It's worthless to begin with....guess that's why they removed it. It was probably fitted to the car because it was one more cutting edge "do-hicky" Porsche could do to a 928.

They all consume oil, more so than the early generation cars....just a fact of life with a GTS...it just depends on to what degree.

Aside from the things Erkka pointed out, it's still a 928 and all the things you need to look for still remain.

AO

If it's an auto (not specific to a GTS, but worth mentioning...) you should check for flex plate preload and crank end play.

cobalt

I don't agree the RDK has come in useful more than once with a nail in my tire it stopped me from getting stranded. Although it has given me a few warnings that were a pain just because one tire was slightly low. 95% of the time it works perfectly.

My car gets frequent oil changes at 2500 mile increments and does not need to be topped off between changes, I wouldn't consider it an issue unless you change your oil less frequently. Every 911 I have owned usually needs a quart every 1500 miles.

Alan

This is not my exerience at all... The way the RDK works there is no possible way there is a differential measurement. Each sensor is binary it either alerts or not. There are only 3 possible states per wheel no alert, only 1 sensor alerts, both sensors alert.

The receiver per wheel just detects these alerts and based on vehicle speed determines if its one or 2 sensors - it has no idea what the actual tire pressure is....

A warning happens even if its only one sensor alerting. Each sensor triggers depending primarily on pressure with some internal compensation for temperature. There are only 2 types of sensors available for RDK: 2.5 bar (~36 PSI) and 3.0 bar (43.5 PSI).

The sensors are many hundred dollars each and you need 2 per wheel - so not very practical to swap out...

Modern aftermarket TPMS are availble (many now) and these have absolute real-time measurements (wirelessly) per wheel and allow you to set custom pressure & temperature warning & alert levels. These are perfect for aftermarket (no sensor) wheels or any case whete you need to run non-standard pressures.

If we could just integrate one into the dashboard warning system...

BTW - my RDK is active and works OK - I run a little higher than stock pressures and also monitor with a smartire system - this is what Porsche should have done to begin with (but technology has advanced a lot since the late 80's).

Alan

928ntslow

If it works for your purposes thats great. From my experience...and other here-say, life moves along quite nicely without it. Besides, once you change out the wheels to more contemporary fittings, the systems needs to be by-passed. As Alan had stated, the wireless sensors are "real" time and wireless which is the way to go. I can only see the value for this in competition environments. The millions of cars on the road without them seem to get along just fine.

Anyway, Porsche felt it wasn't necessary for some reason to have them anymore since they continued the car for 2 more years without them.

cobalt

Interesting. I know it has no idea what the actual pressure is. This past Saturday I took my car to a car show. As I left the gas station from filling up the sensor alerted me that the front right tire was low, I hit the override stalk. I drove for about 40 miles and it went off again. I found a gas station and added air. The gage at the station said I was at 30 pounds so I pumped it up to 40 to be safe because I figured it was not an accurate gage. The following morning my wife drove the GTS and I had the turbo going to another car show. This time the RDK read the front left tire was low. I had a longacre pressure gage this time and it said the front left was at 36 PSI and the front right was at 42. So I dropped the front right to 36 and the warning never came back. This is not the only time this has happened this way.

I had it once go off at an AX event after making a few hard turns in one direction one tire jumped to 44psi and the other at 38psi and it showed the tire that was lowest.

So I might be wrong but I have always found it would read the lower of the 2 either front or rear. So long as all tires were within a few pounds of each other it doesn't go off.

Actually all new cars have to have a tire pressure monitoring system by law.

Vilhuer

928 was only car which used those sensors and Bosch didn't want to do them anymore. I think something like that is more likely reason.

bigmac

On my car, the RDK would give off false warnings every time a weather front came through town. What a pain. On occasion if I drove a few miles and just stopped the car to "re-boot" the system it would be OK.

pmooradian

I wouldn't worry too much about whether the car is an early GTS or a late one. Do all the regular checks you would do for any 928, with special attention to the unique GTS features and the flex plate/thrust bearing condition if it's an A/T.

My RDK worked great if I kept at least 38 psi in the tires until about 2 months ago when the controller box under the dash gave up the ghost. I easily bypassed it. One of these days, I may replace it.

My '93 was made in May '92 and it's had no significant issues in the 9 years since I bought it... 9 years this week actually! It now has 150,000 miles on the odometer and I always drove it like I stole it. I'm confident that my son is now following in my footsteps! He adds a quart of oil on occasion, but it probably leaks more than it burns.

A PPI by a qualified mechanic who knows 928s and careful inspection of the maintenance records are a must. Don't assume if the car has low mileage that it's in good shape mechanically.

Best of luck with the decision!

cold_beer839

I know this is going on in another thread, but I need as much input as I can get from current and past GTS owners. You may not have seen the other thread.

Look at the car in the link:

http://cgi.ebay.com/ebaymotors/ws/eB...263850232&rd=1

It is the one I will be buying if the PPI flies green and there are no major issues in the car's history.

I think $36,500 is a good price for the car in the condition it appears to be in. But I welcome the opinions of the members of this list, so please reply with what you think about this car.

pmooradian

Pics look good.

I guess congratulations are in order!

Depending upon how the PPI looked and if Carfax/history/maint records look good, I think it's a very good price for a 5 spd GTS with low mileage!

Enjoy it!!!