Maintenance & Repairs: 911 vs. 993

[Vytenis]

I have an '87 911 coupe, on which I try to perform the normal maintenance and repairs myself as much as time and expertise permits.

I have read elsewhere that this is more difficult on a 993 due to lack of documentation, resources, etc.

What's your experience?

 

[Brian Minkin]

The primary difference in a 993 is not simple routine maintenance but that it is an ODB2 Diagnostics car and check engine light coming on and needing diagnosis and subsequent repairs to shut it off are not as simple to address as repairs to a 3.2 litre engine as found in your car.  These cars all seem to develope a problem that throws the check engine light especially if they are driven in city traffic rather then wide open.  It invloves a passage in the heads that clogs up and ultimatley can require a top end rebuild on a car with as little as 70K. Still very similar to a 3.2 car to service and do routine maintenance on.  However the injection and emmisions system are more complicated.

[Brian Minkin]

Opps.  Just looked at my post.  Should be OBD2.  I never could type worth a dam!

[Mike Andrews]

Thee are a couple of difference between the two.  But you didn't mention what year 993.

A 1995 993 is OBD1 and the rest are OBD2.  Some prefer the 1995 because of this.

As far as maintenance goes they both use the same amount of oil but the 993 has two filters.  And they are nowhere as easy to get to as the one in the 911.

Twice as many spark plugs in the 993.  And then twice as many wires.  Two distrubutor caps and rotors on the 993.

Hydraulic lifters in the 993 (big plus) that don't need the 15,000 mile (or whatever routine you want to follow) adjustment like the 911.

993 tires are usually more expensive, 17's or 18's versus the 16's on the 911.

Brake pads and rotors are more expensive on the 993.

[BobKalb]

I had the same problem with my engine light coming on.  I have a 1996 twin turbo.  The light came on almost every 25 to 35 miles.  I was told I needed a top end rebuild.  I discussed with my mechanic at CB Foreign cars and  decided that I would try a tier one gas such as Shell Premium.  During the first tank the light came on when the tank was 1/2 full I reset it with my obdII and since then it has not come on in over 1000 miles.  I would try a top tier gas before a rebuild.  Bob Kalb

[bobt993]

Tech section, PCA forum covers this extensively.  There are some ways to remove coking without a tear down of the top end.  Check out the procedure suggested and consider having your mechanic implement it.

[BobKalb]

I know what your saying.  I did investigate other options.   My problem has been solved.  My check engine liget regarding the right bank emissions sensor was coming on every 35 to 40 miles.  Since the swwith to a cleaner burning gas the problem has not shown up again.  It is over 1000 miles since the last engine light episode.