There went my 'good tune'

[isnms]

I decided to try out the Rebic LC. So I installed it and had my S-AFR disabled. Everything seemed to be fine. With my mods, I had the dial set at 3, A/F ~11:1, boost ~11.5psi, 93 octane (first attachment). Felt great and everything looked good.

That was getting on the interstate. Five minutes later getting off the interstate, decelerating down the off ramp, it died. I cranked it back up and had a terrible lope. No acceleration. I babied it the rest of the way to work, about 1.5 mile. Looking at my vacuum reading at idle, it had dropped to ~16.7 and VF climbed to 3.5v (second attachment). I start looking for vacuum leaks. I could not find any. Then I decide to pull the dipstick out and it's blowing smoke like a chimney

I trailer it home and do a compression test:
[cyl]...[dry]...[wet]
1........180.....---
2.........85.....120
3........185.....---
4........185.....---
5........120.....150
6........120.....150
So now I have blown rings or ringland. Either way the motor has to come out.

DETONATION, but I don't know how. Must have been timing.

 

[Nick M]

A loping idle is incorrect A/F. Make sure you have gone over the car completely. The ECU is trying to correct because you have the wrong readings.

You might have missed a hose somewhere. Or might not.

 

[shaeff]

my car will lope at idle like crazy even if i have a small vaccuum line detached. plug it back in, purrs like a kitten.

-shaeff

 

[IJ.]

Damn

Only takes a millisecond.

 

[isnms]

Oh how I wish, but with the chimney like dipstick tube (blow by) and compression in 2.........85.....120 (rings or ringland), I don't think I have a chance. I have searched all the vacuum hoses and ic connections and have not found a leak. :dunno:

edit: Yeah. I was thinking, after that log getting on the interstate, things were going Great!! :wiggle:... :nono:

 

[IJ.]

Isnms: Sorry time to stick a fork in it it's done!

 

[hottscennessey]

That sucks! I hope you get it straightened out. In the previous thread (about the tune) it looked great.

 

[Nick M]

Isnms: Sorry time to stick a fork in it it's done!

That needs to be a smilie.

 

[MK3Brent]

Makes me want to throw in a few gallons of 110 now. :-\

 

[97TSiAWD]

Sorry to hear about your misfortune.

So I take it that there is no software available to log knock counts with these cars?

 

[hottscennessey]

I'm sure my meth injecton has helped me out with this hot weather and my heatsoaking AFM setup, whenever you get it back up and running again you might want to consider it. I love mine.

 

[Fozbo]

Dang, another oklahoma supra down :/.

 

[blackgamer16]

That sucks man- Only means building a bigger and stronger 7m.

Hey if you need any help with anything shoot me a pm;

Blackgamer16

 

[jetjock]

Guess that igniter problem is sorta moot now

Sorry to hear of this isnms. If it helps any I always enjoy your posts. Whether giving or asking advice they're well written, filled with helpful links or graphics and (unlike many) are actually coherent. It'd be nice if everyone did as well.

 

[supra90turbo]

/\ agreed 100%!
This is what happens when the educated have a problem.

Hope you get it running again soon, isnms.

 

[hottscennessey]

^yup, isnms has always helped me out.. and done so very clearly and detailed.

 

[isnms]

Thank you all for the sympathy and those with empathy too

I need to learn something from this and so far can’t put my finger on it. What was the cause? I thought I had a good conservative tune. Was not exceeding the boost reasonable for my mods. I had all supporting mods for this level of tune, so I thought. Only mods not installed yet were the fuel.

So help me out:

• The igniter, that I can’t get to pass an ignition module test, actually is bad and missed a step.
• The Rebic injector driver is driving 15 year old injectors w/ 15 year old pump. The injectors could not handle the greater duty cycle.
  • ^this means get my fuel mods done
• The Rebic does something to the timing that my weak igniter could not handle.
• Other

 

[blk91]

Im not sure but from looking at the Manual it looks like you leaned the Map out by 12% when you set it for 3 because from what i read 5 is stock and 0 is -30 and 10 is plus 30

http://www.mkiiitech.com/forums/viewtopic.php?p=852&sid=b61d3c92854e88bc6678c45571c6aa76

 

[isnms]

That statement, that is posted in many places, does not seem to be accurate.

Instead, if you look at the scanned documentation:
GReddy Rebic LC Manufacture Documentation

At "0", the injectors will flow 5% less than factory ECU settings.
At "10", the injectors will flow 20%~25% more than factory ECU settings.

Indicates '2' to be stock setting.

http://www.mkiiitech.com/forums/viewtopic.php?t=955

 

[suprashy]

isnms:

Sorry to hear about this.

Right now, I too have achieved a good self tune (11.2-11.5's), but one thing I noticed was that I was seeing 870 C EGT's under boost around the 5,500 mark. I immediately stopped testing after that. I am pulling from 22-28% on my S-AFC for my "good tune", and I think the ECU advances timing and is causing the high EGT's. (My timing @ idle is stock). My Supra gurus (I'm new to tuning), also agree this could be true. I think the 680's are too much for my HKS Sport 60-1 @ 15psi. I do have a PT61 on the way which I'm hoping will result in less fuel pulled via the S-AFC, resulting in less timing advance, yielding lower EGT's.

My question for you is did you have an EGT gauge? I know that this displays an average of all 6 cylinders, and tuning should not be done solely based on one EGT probe, but I'm curious if you knew what your EGT's were. I switched to colder NGK BCPR 7ES, and noted a slight 20 deg. drop in EGT's, and the car feels faster.

Please state your turbo/fuel setup, and what psi u were running during your last good run.

From what I've been learning, spark plug condition is one hell of a way to learn about the condition of your engine per cylinder, and I'm surprised I don't see too much of that discussion here. I have no probs. pulling plugs regularly, to ck. on the condition of my engine - its free! U may want to pull plugs and post pics. I think "spark plug monitoring" is essential, and I'm adding it to my "know what's going on in my engine" forte. Prob. with "spark plug tuning" by the time one notices detonation evidence on the plug, its too late. Small incremental changes in tuning I suppose would help.

I'm sorry, I haven't given you an answer, your situation is similar to mine right now - I'm looking at good A/F's, but there seems to be more to tuning than just that. You stated you have old plugs and injectors, but if they were not flowing correctly, your A/F's would lean out. Given what I've exp. I think possibly your timing is being affected?

If I've erred anywhere, please correct me. Good luck, and pls. keep us informed.