Why is my 3.2 so slow??
 

I know there are a lot of guys on this board with 3.2s of various types so maybe you can help with this.

I am the current caretaker of an '89 3.2 cab and of all the 911s Ive come across over the last few years this one has thrown me a curve ball. Im not sure if its just me or something related to the car but the car is simply......... slow.

It has a SW chip and a Dansk 1 out exhaust which seems ok. The car is smooth, has an idle switch problem or something so it stalls occasionally but other than that it drives well. 80K miles, good history, just serviced and everything works on it. Its the performance that Im not sure about. Were these cars not meant to be about 6 sec to 60mph? This car doesnt seem anything like that.

I have a standard test for seat of the pants acceleration and comparing the cars I have this is how I see it:

Rolling start 50mph slightly uphill probably about a quarter mile. At the top of the hill the '75 turbo will be doing over 120mph, the Carrera 2.7 over 100mph but the 3.2 struggles to get to 85mph over the same distance.

Can anyone with experience of these late 3.2s let me know whats going on here?

Boy I'm no expert here what so ever, (wrenches and & are mortal enemies). If the car is in good mechanical condition could it be something as simple as the accelerator pedal not being properly adjustment?@ not getting all you can from it? Can you actually have a mate time you 0-60?
I'm sure a few experts will chime in.

Yeah the gas pedal and throttle position was my first thought also. All looks right though. I was planning on testing it against a friends new Golf GTI. Im worried it might be embarrassing Im afraid to say...

GTI diesel? Hope you can beat that.

Isn't there a full throttle switch that needs to close to get full power?

Do you still have the original Chip. If so put it back in to test. If its not the throttle it sounds electrical to me

Sounds like the car is firing on 5 cylinders...mine will run smooth enough on 5 to do what you describe.

Start basic: fuel filter, make sure all injectors are firing, check all the plugs to see if anything is fouled.

Make sure the throttle gets fully open. Incidentally, the black plastic switch on the side of the throttle body is not a throttle position sensor, it is just a rotary on/off switch to tell the DME its at full throttle and the DME then ignores the o2 sensor. The Bentley manual describes how to test and set all this. When I first got my 3.2 years ago I thought it was a TPS too, but it is not.

If all else fails get to a shop that can stick a wideband o2 sensor in the exhaust and find out what's going on.

Your SW chip is not the problem. If the car is stalling occasionally you have something else amiss.

I had a miss on very humid days (not in the rain, just high ambient humidity) other then that the car ran great, I think the 3.2 runs pretty strong on 5 cylinders. You should check your ignition wires, this is what my coil wire end to distributer looked like and the distributer end of the #4 wire (inside the boot). All the wires unscrew from the ends, worth looking at. When i checked the resistance of my distributer cap the coil post had high resistance and the #4 post was very high in resistance. I think the bad connections destroyed a relatively new dist. cap. Replaced the cap, two dist. end boots and the #4 wire. She idles smoother and has more get-up and go now. The one on the left was the coil boot to distributer, I'm surprise that the engine ran at all, the ignition is designed to have resistance at the spark plug ends of 3k ohms. So the story is even with very high resistance they run pretty well.

http://forums.pelicanparts.com/uploa...1259338442.jpg

IIRC, I've read somewhere that the barndoor (throttle air plate) that is located where the airbox meets the AFM box may sometimes not open completely at WOT, which would probably cause your problem. You should probably remove the airbox and test your barndoor, and make any adjustments as necessary.

To get 6 sec 0-60 you really have to get on it very hard. There are two ways to check the throttle switch. First have someone push the accelerator to the floor and see if it physically opens all the way, then while they are holding it open pull the connector off and put a meter on it and see it it is actuating.
The plug wires which were originals on my 88 started to fail. 15 to 20 years is a long service life for those. I replaced those 5 years ago with Magnacore's. Also if an injector is not operating that can do it as well. These cars can run amazingly well on less than 6 cylinders.

make sure you are getting full throttle.

Do you have the original cat?
The suggestions above seem most likely.
You say "just serviced and everything works on it". I would hope your mechanic could tell if it is running on 5 cylinders. After checking the electrical system and fuel system, consider that your cat might be plugged; it is rare, but often overlooked.

Thanks for the input. I will start checking again to see if it looks like its getting full throttle. I was assuming it would sound different if running on 5 but maybe not?

This car has a cat bypass installed too. I will have a look at the cap and wires and see if anything looks out of place but it sounds like the diagnosis will be beyond my abilities. Will have to go back to the shop to be sorted I suspect.

At least it sounds like there is probably something wrong and its not just unrealistic expectations.

I have a 77 with an 89 3.2 in it. When I got the car it was slow too. It actually ran surprisingly well but was, well, slow. It turned out to be many things:

1) The fuel filter was clogged

2) The 2.7 CIS fuel accumulator was still installed in the fuel system

3) The CIS fuel pump was providing incorrect fuel pressure to the Motronic system

4) One of the plug wires was severely corroded

5) The CO setting was way off

6) The intake boot clamp was restricting the throttle to about 80% open

7) The "brown wire" was jumpered on the ECU

I added a Steve Wong chip and cat bypass and now the car is as fast as I expected it to be. Fast enough to whack the ass end sideways in second gear on a freeway on ramp.

I would suggest you check for fully opening throttle, throttle position switch sensing full open, correct fuel pressure, correct CO setting. Also do a compression or leakdown test to see if you are developing normal compression in all cylinders.

Steve Wong has a good description of how to check the throttle position switch. I think it's on his website 911CHIPS - Performance Chip Tuning for the Porsche 911

I don't have anything to add as far as what the problem may be but when I was looking at cars I drove about 15-20 cars and I recall the 88 I drove felt sluggish compared to most of the earlier cars. I just thought it was weight, G50, refinement, etc... that the earlier cars lacked. I didn't like it as much as the SC's I'd driven. Just sayin.....

I understand your frustration, I have a 87 3.2 that was rebuilt approx. 20,000 miles ago by the PO. His shop bill shows everything was complete including euro pitons and cylinders. Since then I added a SW chip, Bursch exhust, removed the cat, new wires, cap, plugs, rotor,filters and an msd intake. Bottom line, my wifes 02 Boxster still blows it away. Any idea,!

Cam timing off?

Both of you two have something amiss. My '84 with a euro cat bypass and SW chip, and with a little weight removed (it weighs 2550 pounds) is very quick. It's noticeably quicker than my wife's 2.7 liter Cayman, and even gives my 996 a decent run for it's money.

Something's definitely not right if you have a SW chip and a cat bypass and the car still feels slow.

Perhaps something more scientific then how fast a car feels should be our baseline. 0-60, 40-60 in third or fourth. A dyno run?

I can post how many seconds it takes for my car to go from a rolling start (level ground) 2nd gear @ 10 mph to 60 mph. Then a couple of runs rolling @ 40 mph to 90 mph in 3rd gear. Thats a 50 mph spread from 2nd gear as well as 3rd. What do you guys think it should be in seconds to pick up the 50 mph? Off the top of my head I think 5 seconds would mean things are in order.
???

Blacklotus99:

Scott (450knotOffice) is a pretty good barometer for the relative performance of a Carrera 3.2.

I also own an 87 Carrera 3.2 Targa. It weighs 2,460 lbs after a liberal amount of weight reduction (pretty much bare bones). With 180,000 miles on the clock it still flat out flies. The car is very quick as per my butt dyno and relative to other modern cars. I have had the chance to gauge the Carrera's performance in several "safe and sane" encounters over the past 6 years. My car shows every bit as much acceleration as an STi, GTi, Mustang V8, Boxster, S2000, etc... Moreover, it is a hell of a lot more raw, challenging, and rewarding to drive than any of the cars I have mentioned IMHO.

So, something seems to definitely be amiss with your Carrera Cab.

Mike