I apologize for the stupid question, but how do I scan the current misfire counters in hptuners?

I run BP 93 octane, but I notice if I don't run 104+ "advanced" octane boost, I get some entries in the knock retard histogram. If I run 93 octane and the octane boost, I get all 0s in the knock retard table.

I'm running "stock" timing. That is, I've never modified the timing. Should I back it off a little, especially since I'm running 5-6psi on a 10.9:1 motor?

 

I currently don't have any codes. I went over the wiring and it all "looks" good.

No, I did not change the springs. I'm running the "beehive" springs that came on the Dart Pro 1 heads. My cam is 228/232 .571/.573 112, is that too big for beehive springs?

 

So I noticed that one of my plug wires is touching the oil dipstick tube (and tube brace). I ran the car in the garage with the door shut to see if I could see any evidence of a spark jump...I didn't see anything but not sure if I would anyway. Perhaps at WOT under load the spark decides its easier to just jump through to the dipstick? I now remember on my '71 chevelle running solid core 10mm wires and a super coil if you held one of the wires (and they were new wires) you would get a nice jolt, even at idle.

I really hope this is it! I'll try it as soon as it stops raining (I don't get traction starting in 2nd in dry conditions).

 

Thanks for all the help guys, I really appreciate it!

 

Pull your spark plugs, could be as simple as a cracked plug when you did the heads.

 

Just add the current misfire cyl 1-8 pids in the table display. And delete any unneeded pids in order to be under 24 bytes. As that is the max bytes a 1997-98 car will scan properly.

Using the stock 1998 timing table on a boosted car is a very bad idea. The only thing that might of saved your engine it is that your probably running on the low octane table. And you need at least 2 heat range colder than stock plugs and a 160*F thermostat.

Russ Kemp

 

I would assume by timing is ok since my knock retard table shows all zeros, is this this safe to assume? If its using the low octane table, wouldn't I see knock retard in the knock retard table?

What should the timing be?

I would think pulling timing on a 5psi motor would completely negate the amount of power added by the supercharger.

I do have a 160 thermostat, not sure what the plugs are, I know they are colder plugs but I forget exactly what they are.

 

Post your tune, and I'll check out the timing tables vs stock. Also may have the knock sensor tables desensitized.

I would start at 14*-16* WOT spark timing.

Russ Kemp

 

14*-16* wow, I'm twice that. Knock retard table shows 0 in all cells though...not sure if that can be trusted I guess.

BTW: I'm quite rich right now (<10.0) so that's probably "helping" out.

Attached is my tune.

Thanks for the help! So should I basically gradually decrease timing to 16* from .60 g/cyl starting from 2400 rpm? (Main Spark vs. Airmass vs RPM)

I bet it turns out that my surging is "just" spark knock. My car was tuned with everything minus the supercharger by a very reputable tuner...I'm thinking he should have pulled timing with my NA setup as well...but he didn't.

 

This ^^ When I read that I thought we had a winner. That and <10.0 AFR (wow that's rich). My car is boosted too and I'm running 17 degrees timing up top. If you are running a stock timing table I'm surprised you don't have a paperweight right now. LOL. Took me a while to get mine dialed in when I started tuning it. But once dialed in it should run great.

Don't know Russ Kemp personally but see his stuff online. He will get your tune in line. He knows his stuff.

 

Are you saying that the tune wasn't changed at all after the supercharger install? Just looking at your tune, the WOT spark timing is stock. And your misfire detection is disabled!

Any mods to the transmission? As the shift pressures are stock, and the positive force motor table was lowered in an attempt to firm up the shifts. Also the 3-4 shift is at 22 mph. What size rear tires?

Russ Kemp

 

Yeah, I've only just started tuning for the SC. I've had the SC in for a couple of years but I rarely drive the car and I never went WOT...which I discovered wouldn't have worked anyway since the P1514 table would have prevented me from doing so anyway. I've had a WB sensor/gauge since the install so I've always been able to see the AFR.

I remember the previous tuner telling me he was going to raise the shift pressure, not sure what he did though.

Yes, the timing is stock and I just disabled the misfire detection a couple of days ago so my converter would lock up. I tried raising the misfire values but all that did was to stop my converter from locking up at all. My goal was to desensitize the misfire tables to get my converter to lock up, I started by maxing out the tables to work backwards, but that just prevented my converter from locking at all. I've haven't gone full throttle with the misfire detection disabled but I have never seen a misfire code. I can restore the misfire detection but then my converter won't stay locked, which is super annoying.

Are misfire and knock retard related? That is, by disabling misfire detection (which 90 percent of people with cams/converters do) am I also disabling knock retard? I don't want that of course.

I haven't tuned the shift points, but they may have been modified by the previous tuner. The shift points feel fine to me though, I haven't noticed it ever shifting from 3-4 at 22 though. Tire size: 345/35/18.

As far as the tune, all I believe that is modified is:
Idle speed
Fans
Injector tables
MAF table (as per Greg Banish DVD)
VE table (as per Greg Banish DVD)
PE table
Misfire detection (disabled)
P1514 table maxed (I'm going to revisit this)

I think that's it. Car idles well now and my current afr is < 10.... Which is intentional until I get the other issue figured out (the issue this thread is all about).

I'll drop the timing to 16. Should I smooth it in from say 60 g/cyl and 2400? I've looked at some other supercharger tunes from the HP tuners site and that seems to be what they are doing. Although these tunes are 7-10 psi...I'm right around 5 (thats the highest I saw on my gauge anyway).

With the addition of the octane boost (on top of 93 gas) I see 0s in all cells of the knock retard table. Can I trust this histogram? Makes me nervous that it says 0 at stock timing if it really is knocking). Probably the super rich PE I have is helping me reduce knock?

Thanks for the help! I really really really appreciate it!!!!!

 

So I backed the timing off...to 16* max. I made a couple of passes. The problem seems to be significantly diminished, maybe its gone but I want to say its still there as the acceleration didn't seem as smooth as I was expecting.

The knock-retard table shows 0 in all cells (but it did with 25-26* advance as well).

Pass 1:
max advance achieved was 14* (as reported by histogram). Not sure why it didn't hit 16 like specified in the table, but with the stock timing it only reported 25-26 (no knock retard reported), rather than 28.
Power was significantly reduced. Seemed like it had to work hard to get to 6000 rpm (2nd gear). When I had the stock timing it would squeal the tires all the way up to redline and wanted to keep going.

Pass 2:
P0103 code tripped (MAF). First time I ever saw that. I set the low octane table to 10* max and that is exactly what it hit...even less power than before...which is what I would expect.
Why did I trip the P0103? Must have happened right away because the highest timing was 10. What's the deal here?

AFR:
10.3 (I'll eventually dial this into 11.1-11.3).

Thoughts:
16* (achieved 14*) seems way too conservative. My car felt faster w/out the supercharger with this timing.

Next steps:
Increase timing to 19*. With what I've seen thus far it will only achieve 17*. Lean up to closer to 11.0.

I'd like to higher but from everything you've all told me plus everything I've read indicates this is a bad idea. What confuses me is that the knock retard table shows 0 in all cells even at stock timing (93 octane and octane boost). I'd expect to see some knock retard if the engine was reporting knock (as it does when I don't run octane boost).

What are your thoughts?

 

What injectors? As for the misfire, return the temp tables to stock, then max out the low rpm & idle misfire event time tables. This way at low rpm you won't get false misfires from the cam and at higher rpm if you have a true misfire, there will be a misfire code/flashing ses light.

As for the P0103, you may have to raise the Maf fail Hz if your hitting more than 11250 Hz.

If your getting the P1514 code, and that table is maxed on your tune, then you will need to scale your tune by lowering the IFR table & Maf table.

Not sure about your timing issue, I've heard about reluctor wheels slipping on the crankshaft. You will need to mark your crank pulley & a reference at TDC. Then using an adjustable timing light, compare the timing to the scanner. And what was your IAT when the timing was lower than the table values?

Russ Kemp

 

Injectors: 60# siemens deka4

Its the first time I saw the P0103. It must have happened early on in the run as the timing never saw higher than 10* so it couldn't have hit the 11250 hz...or could it?

When I maxed out the low medium and high misfire event tables my converted failed to lock at all. Is this expected?