Ranger_One

At 3000 rpm there seems to be a flat spot in the power output. Any ideas? I bought the car last month. the clock has 10765 on it. P.O. put an Auto authority chip in it, vintage 89'. Fab speed cat bypass is the only other mod.

Thanks,

ago 85 carrera

Me too!

I am thinking first about ignition first. Should I be? The car is a stock 3.2 with no mods and I just bought a set of NGK plugs to see if that fixes the issue. If not, I will change the wires (lotta money for Porsche wires but I'm probably in the minority in not wanting a hotrod looking engine). I know I've gone about 18k on these plugs and much farther on the wires, distributor, and coil.

Would love others' thoughts on this. Thanks.

Andre

theiceman

Introductions ? pictures of car ? .... do you show up at a strangers house and just join the party ?
Welcome to Rennlist ..

TroyN

Welcome. Describe the flat spot a little more, does the car pick up again after it hits the flat spot? Does it seem to misfire at the flat spot? I'd go through and give it a tune-up, replace filters, plugs, etc. to eliminate the simple stuff as the problem. Pics too!

ago 85 carrera

If it's misfiring it's not a misfiring feeling that I know; I'd describe it as a slight loss in power as the revs climb above 3200 rpm. It's most easy to feel in 2nd and 3rd and throttle open wide and I started to notice it about 2000 miles ago. I changed the plugs about 18k ago (3 years maybe) and the rotor cap last year as it was cracked.

I've had the car for a while so my bad for never posting a pic. The munchkin in the pic is in 2nd grade now so though he's changed in look, the car hasn't. My wife doesn't keep a lot of pictures of my car on her Mac... imagine that.

Thanks for the help.

theiceman

Wow nice car .. the white fuchs I thought i would not like but on this car they look great ... You need a Carrera guy but have you ever replaced the O2 sensor ?

butzip

For contestant #2 Check for a clogged cat...... O2 sensor...... bad gas..... for #1 change the chip.....

ago 85 carrera

Thanks Iceman. I think the body color petals work well with Fuchs and 911s.

Weather's been crappy here so I didn't get to replacing the plugs so I'll run another bottle of Techron through the injectors this week and see if that fixes anything. If not, I'll let the group know what resolves the issue when I figure it out.

GothingNC

Cool, another Targa owner from Raleigh

Need to meet the group at Wake Zone Saturday mornings in Apex.

Have you taken it on a long spirited drives "Italian Tune Up" or fueled up at a station using Ethanol?

18k miles seems like a lot of mileage for the plugs

John

John

ago 85 carrera

Hey John,

I used to do the Brier Creek meetings when they were at Caribou Coffee but as that group grew and so did my kids, my time to get there shrunk. So now my P-car outings are to Saturday morning kid things. It's not bad at all, just life's transitions.

I subscribe to the "life begins at 4000 rpm" philosophy so if there's stuff to blow out of the engine I think I'm blowing it out. 18k might be a lot of the plugs (I don't know what's recommended but I think if there's weak spark, the wires might be original and just as suspect.) I hadn't considered the fuel but I don't think that's it as I always fill at the same BP and I only noticed this about 2k miles ago. Anyway, I'm about halfway through my rather scattered "differential diagnosis" and will let this group know what I find causes my "flat spot".

Have you or anyone you know done your own valve adjustment? I think I'm up to the job on a warm weekend but might like someone looking over my shoulder.

Andre

TT Oversteer

Bad plug wires or connectors often cause a miss at idle. If your idle sounds and feels smooth the problem could be a number of things besides wires or plugs.

The fuel filter is an often forgotten maintenance item. If you don't know how long it's been in service you should probably change it.

The 3.2 sometimes suffers from vacuum leaks around the intake manifold to intake port gaskets. Spray some carb cleaner around the intake manifold gaskets with the engine idling and see if the rpm changes.

rusnak

Andre, I agree with the suggestions to look at fuel delivery. You can easily attach a fuel pressure gauge on the driver's side fuel rail. Don't overtighten the cap, and don't lose the little steel ball. You have to jumper the dme relay with a switch to check fuel delivery volume. A LOT of 3.2s are having their fuel pumps go lately. Still, a tuneup and inspection is in order before proceeding.

GothingNC

Andre,

I think the plugs are to be changed every 12k to 15k miles depending upon driving conditions. They could be worn out by now.

My brother in Youngsville used to run a Porsche shop on LI many years ago and has plenty of exeprience with the valve adjustments.

Mine is due within the next 1,000 miles

John