|
|
Post by 96mustang460cid on Dec 20, 2011 9:49:26 GMT -5
This engine is from an 88 T-coupe. The only mods are a rotated upper intake, FMIC, and Megasquirt. It has all new sensors and a tune-up. Tune-up consisted of Ford spark plugs, and parts store brand cap, rotor, and wires. I had the same exact problem before doing the tune-up.
When driving around, the car will cutout. It normally cuts out around 100kpa. Sometimes, it is slightly above or below this point, though. It doesn't seem to be RPM dependent -- 1st gear will cutout at a higher RPM than 5th gear (but still around the same MAP reading). The car starts good and runs good under light load. I am driving the car around town, to and from work, ect.
I am using the ignition table listed in the ignition timing thread on this board. The timing has been verified at 20* when "fixed timing" is selected in Tuner Studio.
I have gone though a couple of junk yard engines (not tune related) before putting this rebuilt engine in it. The first engine could run some boost before it cut out. The last engine acted exactly like this one. I'm at a loss...
I've looked through TunerStudio for some weird setting I accidentally set, but nothing stands out.
Any help, suggestions, and/or guidance would be greatly appreciated! I have tried all the trouble shooting methods I'm familiar with and haven't made any progress.
Merry Christmas!
Michael
|
|
|
|
Post by 96mustang460cid on Dec 20, 2011 9:53:42 GMT -5
In case it's related....
The has trouble getting up to temperature. It runs around with a CLT of 130 - 135*. I pulled the 160* thermostat and installed a 180* thermostat. That increased the CLT to the temps listed above. Because the car is running so cool, it's still adding fuel enrichment while I'm cruising around. I plan to block off part of the radiator to help the engine get to a higher operating temperature.
Merry Christmas!
Michael
|
|
|
|
Post by Stinger on Dec 20, 2011 17:18:05 GMT -5
Got any datalogs of the issue?
Your VE numbers seem a bit high everywhere so it makes me wonder if your required fuel is correct, your MAP based enrichment is correct, etc.
Post the tune and a datalog of the problem, preferably where you hit the space bar to "mark" the spot in the datalog when it cuts out so it's easy to find.
|
|
|
|
Post by 96mustang460cid on Dec 22, 2011 10:06:12 GMT -5
Okay, I think I attached the log correctly. This log started about a minute after starting the car this morning and continued for my entire drive to work.
Mark #1 = 462.987 seconds
Mark #2 = 463.354 seconds
Mark #3 = 468.410 seconds
This set of events was when I was getting onto the turnpike and slowly accelerating through the gears.
I think the tune is attached to the log file, but am not sure if it works that way. Just in case, I will do a second post and attach my current tune.
Merry Christmas!
Michael
I guess the file is too large to past. I will take a screen shot and attach the picture. On the way home today, after work, I'll do a shorter log and attach it.
|
|
|
|
Post by 96mustang460cid on Dec 22, 2011 10:07:40 GMT -5
This post should have attached the current tune (as of this morning).
Merry Christmas!
Michael
|
|
|
|
Post by 96mustang460cid on Dec 22, 2011 11:09:28 GMT -5
I was just reading through my initial post and realized that something I said may not be entirely clear.
The MAP reading where it normally cuts out is 100kpa (absolute pressure. Not gauge pressure). In other words, as soon as I get close to getting 'boost', it starts to cut out. My vacuum/boost gauge is right around "0".
Sorry if I didn't state that clearly.
Merry Christmas!
Michael
|
|
|
|
Post by 96mustang460cid on Dec 22, 2011 12:01:08 GMT -5
Got any datalogs of the issue? Your VE numbers seem a bit high everywhere so it makes me wonder if your required fuel is correct, your MAP based enrichment is correct, etc. Post the tune and a datalog of the problem, preferably where you hit the space bar to "mark" the spot in the datalog when it cuts out so it's easy to find. I was looking at the tune found the required fuel. It was setup for a 350 cid, V8, with (8) 30 lb/hr injectors and was set at 6.6 [ms] (I think), I believe. Upon entering the correct info, the required fuel is now 5.30 [ms]. I will post back how this affects everything. I should have done a better job verifying the tune I received from Turbo_Dad. In his defense, though, I'm working my way through a steep learning curve that I'm sure has and continue to goes through lots of mistakes. Merry Christmas! Michael |
|
|
|
Post by Stinger on Dec 22, 2011 14:06:12 GMT -5
You should be able to attach the actual log file (.msl) to this forum, unless it's too big. In that case, you can upload it to any file hosting site (megaupload, mediafire, etc.) and post the link here.
That Req Fuel error (and fix) as I suspected above was at least part of the issue, should put your VE table numbers at a more reasonable value throughout the table (which is good). It most likely won't fix the misfire issue though. You should need to pull a significant amount of fuel out of the fuel table after making this change since your idle numbers should be in the 30's or 40's and your midrange 100kpa numbers should be in the 70's or 80's.
Looks like your injector staging (in the same window as required fuel) should be changed to 2 squirts alternating or 1 squirt simultaneous.
|
|
|
|
Post by 96mustang460cid on Dec 23, 2011 0:17:29 GMT -5
I corrected the required fuel and have leaned the VE table out a LOT. Between the VE analyzer and heat maps/VE table( (manually edited), I am getting the car to boost well. I have spent a bit of time working up to 160 kpa and am continuing to work my way up from there. I 'think' the factory IHI setting is ~14 psi. Once I get the engine running well at that boost setting, I'll increase the boost to ~20 psi...which, I believe, is considered the max recommended setting for the IHI turbo.
I have blocked off about 60% of the radiator and unplugged the fan until I buy a wire up a fan/temp controller. Even so, the engine only comes up to ~150*F while cruising.
Stinger: you were definitely in the ball park with the VE numbers you tossed out there.
30 kpa = low 30's
100 kpa = 60 - 70's
Stinger, I appreciate your help!
Merry Christmas!
Michael
|
|
|
|
Post by Stinger on Dec 26, 2011 21:33:41 GMT -5
I'd consider 20psi with the IHI to only be the max on race fuel in a drag race situation. If you want the turbo to last any amount of time and not super-heat the air, you'd be better off at 18psi or less.
Hopefully the blocked off radiator is ONLY blocking airflow to the radiator and not to the intercooler as well. If not, you need to modify it so this is the case.
Good to hear you are now into the VE table values I stated it should be in above.
|
|
