Can't rid of engine pinging with Wilk's PowerProm 2, NEED HELP!

[paitken76]

First off, this isn't at all a post bashing Wilk's PowerProm, I love it I'm just having issues fully enjoying it. Here's the deal. I bought the chip a while back, sort of a long while back... and before installing it I did what FR suggested. I had the engine fully checked since the O2 Sensor would mask engine issues that would suddenly arise later with the chip. The car was already in great shape, GREAT. Serviced regularly and even serviced when it didn't need to be, just to keep it up. Relacing this and that. Point is was doing better than great and I had it completely checked before installing the chip. OK now that I got that over with, here is the problem:

In stock mode (PowerProm 2), I ran just fine and it was actually a smoother run that with the stock chip. In performance mode, DAMN it was cool, sounded nice, ran nice but if I actually drove it like a Porsche and not like a Chevy Cavelier it started to ping like crazy so I would let off. It was a bad tease over and over again. Ready....set.... goooooo - uh no. I checked everything, tried everything. Lower octane gas, higher octane gas and then FR suggested that I adjust the FQS to -3, even though if it wasn't octane I would have thought to do the reverse, maybe +3 thinking it wasn't getting enough gas. In any case I need a fix. I haven't been able to use the darn thing since I got it and I've been trouble shooting this issue for the past year.

Here are a couple side items I tried messing with since I've exhausted engine checks, item replacements (sensors, senders, hoses etc). I tried using 87, 89, 93 octane gas. Runs better on the 93, much better, (the car came set for a minimum of 91 octane, gas cap says use 91 RON Unleaded, and I believe the PowerProm was set to 89?) I tried using better plugs. From the standard copper, to the Bosch +2 Titanium and the newer Bosch +4 Iridium. I tried retarding the fuel mixture by -3 as suggested by Wilk. Nothing.

What's the problem? What's the fix? Anyone having issues as well? What can I do?
FR, any thoughts?

It's an 88 Porsche 944 NA, all stock restoration project.
All help and suggestions genuinely and greatly appreciated. Thanks

[Warwood]

You have 10.2:1 compression motor, not the 9.5:1 compression that all of the 86 and earlier 944's have. I think (could be wrong) that Wilk's chip is to hot for you.

Just my $.02.

[mlue]

Originally posted by paitken76
I tried using 87, 89, 93 octane gas. Runs better on the 93, much better, .... I tried using better plugs. From the standard copper, to the Bosch +2 Titanium and the newer Bosch +4 Iridium. I tried retarding the fuel mixture by -3 as suggested by Wilk. Nothing.

What's the problem? What's the fix? Anyone having issues as well? What can I do?
FR, any thoughts?

It's an 88 Porsche 944 NA, all stock restoration project.

You have the high compression NA engine ! The spark advance curve in the performance mode maybe too radical for the higher compression of this NA engine.

Try running:
1) strong fuel injector cleaner to clean injectors so the spray pattern is "fan shaped" and to cleanup deposits in the combustion chambers.

2) using spark plugs with a colder heat range.

3) make sure fuel pressure is good and consistant.

4) octane booster.


I hope that helps.

[paitken76]

But I purchased the PowerProm 2 created for the 1988 944 NA..... FR would have made adjustments for the compression difference. I did try injector cleaners for a few months. About three months ago I bought new ones. Engine ran incredibly better with brand new injectors but it didnt do anything for the pinging in performance mode. I checked the pressure and the dampners when I did the injectors. I thought about the octane booster idea as well this morning. Thanks for that. But something bothers me about adding an octane booster intoo one of our cars. Come on.... its a Porsche, octane booster? Thats what I was telling myself. But could our 944s actually benifit from those? And which brand is best? Concerning the spark plugs, interesting. But I dont follow exactly. How do I know what plugs have a colder heat range? And what does that do? Thanks.

Slight Update / More Info:

Oh, I took it out at lunch and drove it to speed gradually without giving it much gas. Really about 2/3 the amount we would depress the accelerator at any given time / gear. No ping. But thats lame. I got there, but its like doing 0-60 in 20 seconds. I cant drive this sweet ride that! But does that tell you anything? Not enough gas for the spark, or not enough spark for the gas, or what? I didnt look exactly but eyeballing it seemed like anything over 3200 RPM would ping. If I act like grandpa Sunday driving on a local road...then alls good.

Calling FR Wilk..... Any chance this chips a lemon (hee hee) or accidently sent me the wrong one? Come on bud talk to me

Cheers.

[DannoXYZ]

Try adding a gallon of xylene ($7 at home depot) to raise your 93-octane tank to 96-octane and see how it works. Your injector wiring may be corroded as well, leading to a single cylinder running lean. Here's how to test the injector harness:


Here's another test for the injector connectors, lets you track which one, or more is bad. The 1st set of tests checks for proper operation of the +12v power line to the injectors and the 2nd continuity tests check for the condition of the ground (activation) wires on the injector harness.

1. disconnect DME
2. disconnect idle-stabilizer, CV-cycling valve
3. disconnect all injector connectors, be careful to remove the spring-clip first, then pull on the connector, don't pull on loop of wire.

POWER-LINE TEST

4. using battery-ground as ground, use a voltmeter to check for +12v on each pin of injector connector
5. all rearward pins should have +12v
6. all forward pins should have ZERO volts
7. if you have ANY voltage on the forward pin, then you've got a short in that connector.

GROUND LINE TEST

8. Also check ground pairs (forward pin)
9. set voltmeter to ohms and check continuity between forward pins of injector #1 & #2: should read zero ohms (connected)
10. check between forward pins of injector #3 & #4: should read zero ohms (connected)
11. check between forward pins of injector #1 & #3: should read infinite ohm s (not connected)
12 check between forward pins of injector #2 & #4:should read infinite ohms (not connected)

[fast924S]

First try E-mailing FR, Im sure he is more then willing to help you out, I would stay at 93 octane and switch back the fuel control switch on the DME, if it still pings try adding octane booster until the ping stops. Also what does the temp on you P-car run at?? How is the cooling system, Whats the weather like??? You may be running to hot. Are there any other mods done to the car??? Also are you sure its pinging???

[paitken76]

Thanks to all who have made suggestions thus far, Appreciated. And thanks DannoXYZ for the test procedure. I'll give that a try tomorrow afternoon. Whats Xylene? Scared to add a Home Depot product into my car. Details? Fast 924S, the cars temp is good. Doesnt sit on a marker but it sits around 9 O'Clock usually and then around say 10 after running for a while. Doesn't touch the next marker at 11 O'Clock. She gets Phosphate free 50/50 mix. Yes its pinging. I thought maybe it was something else when I first installed the chip, so I started checking everything I could then I took in to a friends shop. Confirmed, it's pinging. (The ol' jar of BB's pouring over a tin roof sound) Concerning temp, it does so anywhere on the temp scale. Warm or hot ....give it gas, she pings. No mods to the car except for Wilks Chip. Everything is stock. Everything I've replaced is stock. I've painfully been trying to keep her true to her colours over the years. The weather, Ha! Atlanta is called Hotlanta for a reason. This state is usually hotter than h*ll, and humid. But right now its sunny and around 82, then rainy and 65-73 the next day. Back and forth. It's our Seattle season. Where you thinking of something else if it wasnt pinging?

[fast924S]

Reason why I asked about the weather is beacues it can effect engines performance. I wasnt really thingking of anything else, I just wanted to make sure the facts are correct so I can brain storm better. When you switched the FQS back what type of fuel where you running??? HOw long did you run it like this?? Have you heard from FR yet??

[DannoXYZ]

"Whats Xylene? Scared to add a Home Depot product into my car. Details? F"

Check out the FUEL FAQ section on my 951 RacerX website. Basically you're adding a 117-octane hydrocarbon to your gas and get the weighted-average increase in octane. The other additive toluene is widely used by the refineries to boost-octane and it's actually a major component in race-gas. However, toulene is harder to get in volume and it's only 114-octane vs. xylene's 117. Basically by adding toluene to your gas, you're making your gas more similar to the European brew.

[paitken76]

Wow, didn't know a thing about that. Very cool, and thanks so much for the link. (Am checking it out) I emailed FR Wilk right after installing it, he asked if I had checked the car out as he asked we do before installing his chip. I did. Later he said to adjust the FQS to position 2 (-3 Fuel). I emailed him again several months later but nothing. Thats was about the time when he dropped off the map. Glad he's back but anyone know what happened to him? Anywho I emailed him just last week mentioning I had the issues still, he said adjust the FQS to -3. Unfortunetly I didnt get more than that.

[pokey]

His computer crashed and he was working on other stuff (see the thread about his new goodies), so it took a while for him to fix it.

[mike944]

Have you taken a look into the spark plug hole with a flashlight? Is your piston and combustion chamber crudded up with carbon? That will both increase your effective compression ratio, and it will create hot-spots for pre-ignition (pinging)

Also, was your head ever surfaced? Porsche heads have VERY little extra material for surfacing. if the shop too off too much, that will raise your compression ratio very quickly. If it was surfaced properly, was the thicker head gasket used at reassembly?

Also, is your car an S? I believe the S's have knock sensors (i'm not sure though) Are they connected and functioning properly? There's a test procedure in the manual. It involves running the engine at idle, and tapping on the sensor retaining bolt with a small hammer, and see if the idle speed changes.

[paitken76]

Mike944 : No I haven't done that but about three months ago I purchased an engine reseal kit. Had the head cleaned at that time, not resurfaced. Just cleaned and checked. All was fine. And at time of reassembly everything was cleans and spotless. All I would expect to find in there now is crud from all the pre-ignition. My P-car is an NA.

Pokey : Glad to hear FR Wilk didnt dissapear for anything major.

DannoXYZ : Very nice site! Tons of info. One guys remarks said he put two gallons of Toulene in his car and next was going to try three. Wow! How much Toulene or Xylene have you dared put in your car safely and without damage?

[DannoXYZ]

There's no safety or damage issue with toluene or xylene as it's a more stable aromatic hydrocarbon tahn most components of gasoline. If you look at the %-composition of aromatics, the Europeans have about 10% more than us. That comes out to about 2-gallons per tank.

Both toluene and xylene have higher densities than gasoline, so you end up with richer mixtures if you add significant amounts. This is not necessarily a bad thing as a richer mixtures tend to be less detonation-prone. However, significant amounts of tolueen, like the 80% mixture that the Honda/McLaren team was running in their late '80s 1.5L 1000bhp+ F1 cars, required heating it up to 140-F in order to aid vaporization and fuel-economy. I figured adding up to 4-gallons per tank of 91-octane pump-gas to yield 96-octane should be fine.

Not sure if that would really help in your case, because you shouldn't be at the limit of compression or octane with your configuration. I still suspect that one or more of your injector wires is corroded, giving you a lean cylinder or two. Simple quick way to test is to pull all the plugs and see if they're all evenly the same color, or maybe one of them is really white, which would indicate a lean mixture.

That head job is a clue as well. About 20% of the people who upgrade their injectors ends up with bad injector wiring due to the age and crispiness of the wires.

--------------------------------------------------------------------------

BTW: Note that aromatics are NOT alcohols, which are straight-chained hydrocarbons with an -OH at the end. This makes the alcohol a polar compound with excellent solvent capabilities in leeching the oils out of your rubber hoses and stuff. That's why alcohols are limited to less than 10% in all gasolines.

[paitken76]

Thanks again for that suggestion and for the thorough post reply. I'll check the plugs tomorrow and let yo uknow what I find, as well as what the injector lines turn up. However the reseal/head job/replaced injectors was all done after the pinging issue came up. (Which happened the moment I installed FR's chip) I will look into both these suggestions though and report back my findings. I stopped by Sherwin Williams at lunch today btw and they didnt have Toulene or Xylene. I'll try lloking at Lowes or Home Deopt later in the week. They gave me a funny look though when I walked in asking for Toulene, Maybe they put two and two together! I pulled up in a friends 951 and my brother tagged along in his Elise. Makes me think they might of had it but didnt want to fork it over lol
I'll try sending FR an email later this evening as well to see if he has any more insight to offer on his end. Thanks again.

[DannoXYZ]

Heh, heh...must be Homeland Security putting pressure on Sherwin Wiliams and Home Depot. I picked up a couple gallons of xylene last week at HD, but they no longer carry the gallon cans of toluene, just tiny pint sizes. Toluene can be used to make TNT- TriNitroToluene and is also used for meth and crack production.

Do you still have the stock chip? Try that and see if you still have the pinging issue. That would immediately pinpoint or clear the Wilk chip as being the problem...

[bigyagi]

hmm, this sounds a little familiar. i had quite a bit of "pinging", not long after installing my dual chip. cut a long story short, my problem was that the eng temp sensor, and the air temp sensor in the dme went south, way far south, and after replacing these items, all was restored. i believe that your car has a "knock" sensor, so it wont be the same for you. i was thinking about the head all carboned up too, but you have addressed this. sounds like danno may have the answer, but it will be something that is out of spec, that is preventing you from enjoying the full benefits. its just a bugger, finding it, right !
keep going, you will get there !
regards, bob.

[DannoXYZ]

No knock-sensor until the 944S with the later Motronic boxes. The KLR computer in the 951 is what monitors the knock-sensing and ignition-retard. But looking at the shear numbers of 951s that have had blown-headgaskets, you can be asurred that the algorithm doesn't work very well...

[paitken76]

Thanks all,..... Danno & Bob,

Funny isn't it! I think I might drive around shop to shop during the week and get all I can, if I can, before my name appears in a deck of cards. lol. I do have the stock chip, GREAT IDEA. (duh) Although like I said it didnt get ping until installing Wilks chip like bigyagi.

Ok let me get this all in order:
1. Reinstall stock chip to check if in fact it's Wilks chip or not. (ping or no ping)
2. Check spark plugs for signs of injector issue / wiring issues. Check wiring to injectors.
3. Replace engine temp sensor, either for a fix or just for *****s and giggles. Can't hurt.
4. Replace air temp sensor in the DME, either for a fix or just for *****s and giggles. Can't hurt. (I'm hitting a brain fart) am I missing something? Air temp sensor in the DME itself or are you referring to the sensor in the AFS? Cant replace that can you? Just the entire AFS. Remind me or inform me if you dont mind. I'm confused as to the part you are referring to.

I dont think I'll be able to get to it all until this weekend. late nights at work this week, unless I can get a day off. We'll see. If you get a new thought lemme know. Otherwise I'll address this all between now and Sunday and get back to all.

Thank you VERY VERY much!

[bigyagi]

the eng temp sens is a doddle to replace, but you are correct, if the air temp sens is done, then its a new afm. unless you can do magic tricks, or are extremely blessed with dexterity! if you go to clarks garage, under sensors, you will find all the info on the sensors, like resistance etc. i believe that for the eng temp, and the air temp sens, the range is the same. the mean range is between 1.45 k, and 3.3k. you can check at various ambient air temperatures, but if they are outside these figures, especially on the low side, then this will cause a lean condition, and "pinging". for example, my eng temp sens, was 0.92k, and the air temp sens was 0.62k. mega well outside the range. replaced, and big broad smile again. i did have slight "pinging"b4 i installed the dual chip, but because of the advance/fuel map, it really brought the message home that something was up. i drive like an old fart most of the time, so the "pinging" was never an issue.
hope this helps, even if only so you can check your readings, and cross off another item.
regards, bob.