Search found 579 matches

by Chucko
Wed Nov 20, 2019 11:55 pm
Forum: Tuning the EEC....
Topic: What would cause fuel pump to prime with key off?
Replies: 10
Views: 496

Re: What would cause fuel pump to prime with key off?

EDS50 wrote:
Mon Nov 18, 2019 6:46 pm
Faulty ignition switch/harness connector?
I can't tell you how many times I've had to reassemble the pieces of my ignition switch... definitely not one of Ford's better ideas.

Usually it fails open, though, not shorted.
by Chucko
Wed Nov 20, 2019 11:54 pm
Forum: Tuning the EEC....
Topic: What would cause fuel pump to prime with key off?
Replies: 10
Views: 496

Re: What would cause fuel pump to prime with key off?

I've had that happen with the original FPR in my '89. I gave it a good rap with a wrench and it stopped. Hasn't happened again.

A new relay is cheap insurance if you're nervous.
by Chucko
Sun Sep 15, 2019 11:12 pm
Forum: Tuning the EEC....
Topic: GUFB/A3M1 decel fuel leanout - running log
Replies: 4
Views: 297

Re: GUFB/A3M1 decel fuel leanout - running log

That's good info Chris, thanks. I'm in no danger of blowing anything up because this is N/A at closed throttle. The fuel multiplier is effectively 1/lambda, so your experience suggests multipliers of about 0.85 are on the border of lean misfire. Since I have an idea what no fuel feels like, I think ...
by Chucko
Sun Sep 15, 2019 3:19 pm
Forum: Tuning the EEC....
Topic: GUFB/A3M1 decel fuel leanout - running log
Replies: 4
Views: 297

GUFB/A3M1 decel fuel leanout - running log

Today for the first time I tried decel fuel leanout (non-zero values in FN374). I've been running with DFSO for years, but got tired of the clunking. I was never brave enough to try shift DFSO. So I started out with .9 as the leanout multiplier, then cutting it to .88. It seems to be working, lookin...
by Chucko
Mon Aug 05, 2019 11:26 am
Forum: Tuning the EEC....
Topic: 2.3 turbo. Constantly rich at idle
Replies: 4
Views: 440

Re: 2.3 turbo. Constantly rich at idle

Is the O2 sensor upstream or downstream from the turbo? If it's downstream, it could be cooling off at idle.
by Chucko
Mon Jul 29, 2019 10:56 pm
Forum: Tuning the EEC....
Topic: maf curve points
Replies: 4
Views: 461

Re: maf curve points

OBTW my rough calculations say if that thing will rev to 6000, you're looking at roughly 1540 kg/hr at 100% VE (load). So don't cut off the top of the curve!
by Chucko
Mon Jul 29, 2019 10:50 pm
Forum: Tuning the EEC....
Topic: maf curve points
Replies: 4
Views: 461

Re: maf curve points

Take the top point on their curve and duplicate it at 16V. Then you can pretty much lop off anything below 20 kg/hr at the low end - your 427 will never get that low except during cranking, when the MAF is ignored anyway. If it's anything like my 37 point curve, some points will be much closer toget...
by Chucko
Sun Jul 28, 2019 1:16 am
Forum: Tuning the EEC....
Topic: Fuel pump prime time pid?
Replies: 16
Views: 2030

Re: Fuel pump prime time pid?

In my head the best I can make of the difference in this case is an opcode that references a register that holds a pointer pointing to the data that the opcode operates on vs an opcode where the data is an operand (no pointer). Is that at least in the neighborhood of being the difference? Yeah, tha...
by Chucko
Sun Jul 28, 2019 1:14 am
Forum: Tuning the EEC....
Topic: Why does my Decel/dashpot/declutch idle fall below DSDRPM
Replies: 10
Views: 568

Re: Why does my Decel/dashpot/declutch idle fall below DSDRPM

cgrey8 wrote:
Sat Jul 27, 2019 3:21 pm
I had this same problem because I like to activate DFSO which closes the ISC and cuts fuel.
That hasn't been my experience with DFSO. Several years of logs tell me it doesn't affect dashpot at all.
by Chucko
Sat Jul 27, 2019 3:11 pm
Forum: Tuning the EEC....
Topic: Why does my Decel/dashpot/declutch idle fall below DSDRPM
Replies: 10
Views: 568

Re: Why does my Decel/dashpot/declutch idle fall below DSDRPM

Paulie's right. The stall-on-declutch problem is pretty common in modified engines, and increasing DASMIN will fix it. Another way is to increase DASPTO, this is the approach I used initially. Two ways to achieve the same result. Take a look at FN875N to find the correlation between lbs/min and RPM....
by Chucko
Sat Jul 27, 2019 3:05 pm
Forum: Tuning the EEC....
Topic: Fuel pump prime time pid?
Replies: 16
Views: 2030

Re: Fuel pump prime time pid?

The GUFx code, and probably lots of other strategies, are organized such that the code itself doesn't change between calibrations. Only the constants, functions, and tables differ. Those have PIDs associated with them. This is a "hack" because you have to modify the code itself. There are several ot...
by Chucko
Fri Jul 26, 2019 9:30 pm
Forum: Tuning the EEC....
Topic: Fuel pump prime time pid?
Replies: 16
Views: 2030

Re: Fuel pump prime time pid?

The fuel pump prime time in GUFB isn't a calibration PID, it's an immediate constant in this code: ################################################################# # Tasklist Routine at 2151, routine offset 2E # Update fuel pump enable. Skip if flag set. # turn pump off if more than 1 sec elapsed s...
by Chucko
Tue Jul 23, 2019 10:08 pm
Forum: EECGeeks
Topic: Proposed GUFB patch tweak
Replies: 33
Views: 1958

Re: Attn: CGrey8 - proposed GUFB patch tweak

sailorbob wrote:
Tue Jul 23, 2019 3:51 am
Chucko wrote:
Sat Jun 29, 2019 1:04 pm
The original code has the same behavior.
My apologies, the original has this same flaw too. Sloppy coding :roll:

BTW, jne and jnz are the same instruction.
Hey, so my patch is bug-for-bug compatible!! :mrgreen: That's the best outcome a maintenance coder can hope for.
by Chucko
Tue Jul 23, 2019 10:06 pm
Forum: Tuning the EEC....
Topic: BZZRPM seems to have no effect (GUFB)
Replies: 7
Views: 656

Re: BZZRPM seems to have no effect (GUFB)

The PIP Legend defines BZZTM Unit as seconds in the GUFB. Factory default is 10 seconds for A9L. I do see in the GUFB98 Excel that the equation is X/8. BZZRPM and many other idle scaler equations are also X/8. So if the disassembly shows a value of 80 then the 10 second default in the a9l is correc...
by Chucko
Mon Jul 22, 2019 9:40 pm
Forum: Tuning the EEC....
Topic: BZZRPM seems to have no effect (GUFB)
Replies: 7
Views: 656

Re: BZZRPM seems to have no effect (GUFB)

By going over the disassembled A9L listing, I figured out what the issue is. BZZRPM and BZZTM are in fact working. It's just that we have the wrong scale factor for BZZTM - it's in seconds, not 1/8 seconds. The factory value is 80 seconds, not 10 as we thought it was. So it's unlikely any of us wait...
by Chucko
Sun Jul 21, 2019 1:01 am
Forum: EECGeeks
Topic: Proposed GUFB patch tweak
Replies: 33
Views: 1958

Re: Attn: CGrey8 - proposed GUFB patch tweak

It worked. I had a little glitch at first because I buggered the opcode for the AD3W. Got that sorted and it works fine.
by Chucko
Sat Jul 20, 2019 5:35 pm
Forum: EECGeeks
Topic: Proposed GUFB patch tweak
Replies: 33
Views: 1958

Re: Attn: CGrey8 - proposed GUFB patch tweak

Sailorbob was right, I was making a mistake. None of the loads or stores were setting the condition flags, so the JNE couldn't make the right decision. So I revised the patch: 84B2: ldw REG_42,#$84EE ldw REG_14,[REG_42++] 84B9: ldw REG_1C,[REG_14] stw REG_1C,$0D00[REG_14] ad3w REG_14,Zero,[REG_42++]...
by Chucko
Thu Jul 18, 2019 9:33 pm
Forum: Hardware Discussions
Topic: Power drop over 3800-4000
Replies: 21
Views: 972

Re: Power drop over 3800-4000

Is the TFI module Motorcraft or off-brand? When my original TFI died (thermal intermittent), I got an off brand, and my car had a bad stumble under heavy load, right when it got into the heart of the torque curve. Replaced it with OEM Motorcraft, no more stumble.
by Chucko
Wed Jul 03, 2019 2:13 pm
Forum: EECGeeks
Topic: Proposed GUFB patch tweak
Replies: 33
Views: 1958

Re: Attn: CGrey8 - proposed GUFB patch tweak

What you are seeing is the affects of background loop starvation. The less often the background loop gets to execute, the less often you get a new advance value. And the faster the engine spins, the more the higher priority code (aka ISRs) are getting run. At 5000RPMs, you might not get a complete ...
by Chucko
Sat Jun 29, 2019 11:46 pm
Forum: EECGeeks
Topic: Proposed GUFB patch tweak
Replies: 33
Views: 1958

Re: Attn: CGrey8 - proposed GUFB patch tweak

86GT wrote:
Sat Jun 29, 2019 3:05 pm
My take on this is:
if it's not broken don't fix it.
I expected this response and I understand the reasoning. But c'mon, we're all hot-rodders! :mrgreen:
by Chucko
Sat Jun 29, 2019 11:38 pm
Forum: EECGeeks
Topic: Proposed GUFB patch tweak
Replies: 33
Views: 1958

Re: Attn: CGrey8 - proposed GUFB patch tweak

Thanks for the detailed info, Clint. That's exactly what I wanted to know. On the other hand if the parameters in the internal registers are not being updated at the rate of 8.4 us then there is no need to update the patch code. Parameters like temperature are slow reacting and do not require a fast...
by Chucko
Sat Jun 29, 2019 11:35 pm
Forum: EECGeeks
Topic: Proposed GUFB patch tweak
Replies: 33
Views: 1958

Re: Attn: CGrey8 - proposed GUFB patch tweak

sailorbob wrote:
Sat Jun 29, 2019 1:28 pm
The original code does not have this flaw, look at what you are loading into 0x0014 on the first pass through.
It presumes the start of the payload list has been moved 4 bytes to make room for the 3-byte-longer patch.

Maybe I should have been a little clearer about this.
by Chucko
Sat Jun 29, 2019 1:04 pm
Forum: EECGeeks
Topic: Proposed GUFB patch tweak
Replies: 33
Views: 1958

Re: Attn: CGrey8 - proposed GUFB patch tweak

Your modification risks crashing the code as the check for the zero marker will be missed if there are no datalog payload items. You are also reducing the number of payload items. The original code has the same behavior. It always copies at least one word unconditionally. It's straightforward to re...
by Chucko
Sat Jun 29, 2019 1:01 am
Forum: EECGeeks
Topic: Proposed GUFB patch tweak
Replies: 33
Views: 1958

Re: Attn: CGrey8 - proposed GUFB patch tweak

I'm pretty sure that DJNZ is a PC relative jump, and doesn't need adjusting.

I've been working from an A9L disassembly (thanks, fellow geeks!). The 0x852F restriction is the end of the calibration console routine that this patch overwrites. I know this is a hard limit.
by Chucko
Fri Jun 28, 2019 3:50 pm
Forum: EECGeeks
Topic: Proposed GUFB patch tweak
Replies: 33
Views: 1958

Re: Attn: CGrey8 - proposed GUFB patch tweak

The difference is the original code reads the next location from memory twice. I rearranged it to eliminate the duplicate read. The loop itself is shorter, but the initial read now happens outside the loop. The code that follows simply initializes the 8 calibration ROM pointer registers at F0 - FE. ...
by Chucko
Thu Jun 27, 2019 11:14 pm
Forum: EECGeeks
Topic: Proposed GUFB patch tweak
Replies: 33
Views: 1958

Proposed GUFB patch tweak

I was farting around with the 8061 documentation, and took a look at the patch in the GUFB strategy document that copies the 0-page (internal register) locations out to where the QH or TwEECer can observe them. The existing code looks like this: 84B2: ldw REG_42,#$84EE 84B6: ldw REG_14,[REG_42++] ld...
by Chucko
Sat Jun 22, 2019 2:30 am
Forum: EECGeeks
Topic: Added useful docs into openEEC in github
Replies: 12
Views: 1092

Re: Added useful docs into openEEC in github

Thanks, ironmanisanemic!
by Chucko
Fri Jun 21, 2019 7:22 pm
Forum: EECGeeks
Topic: Added useful docs into openEEC in github
Replies: 12
Views: 1092

Re: Added useful docs into openEEC in github

Bringing this thread back from the dead...

This Github site is a tremendous resource! Thank you.

Signed, a former assembly language programmer.
by Chucko
Thu Jun 20, 2019 10:12 pm
Forum: Tuning the EEC....
Topic: BZZRPM seems to have no effect (GUFB)
Replies: 7
Views: 656

Re: BZZRPM seems to have no effect (GUFB)

According to the GUFB doc, it's a buzz-up RPM adder that's only in effect for the BZZTM time period (usually 3 seconds) after startup. I don't recall that I've ever used that scalar or even attempted to. Although looking at my tune, I see that my BZZTM is set to 5 (stock for both A9L & X3Z is 10). ...
by Chucko
Thu Jun 20, 2019 9:31 pm
Forum: Tuning the EEC....
Topic: Modified GUFB def if anyone wants it
Replies: 5
Views: 538

Re: Modified GUFB def if anyone wants it

Hey, my intent had nothing to do with politics. I just wanted to compare airflow #s without doing unit conversions.

My beef with the Fox bodies is that everything in the drivetrain is English, and everything in the chassis is metric - and odd metric at that. (Who else uses an 18mm??)