Engine flatlines/jumps

[Aeroking]

Re: Engine flatlines/jumps

i pulled the distributor out this morning. Its an aftermarket distributor, and has the "old style" pickup coil, where the pickup coil is on one side of the distributor. NOT the stock kind that has the points all around the reluctor.

Anywho, the reluctor wheel contacts were hitting the pickup contact. The reluctor wheel is held vertically by snap rings on the top and bottom. The bottom one was broken and laying on the distributor deck.

So i'm gonna put a new snap ring in, set the point gap, and put everything back together. See if that made a difference to solving at least one of the problems.

 

[ziembic]

Re: Engine flatlines/jumps

It is nice to look for something that is broken and actually find something. Hopefully this could be your problem overall. Right at 5k rpm, that wheels could be resonating up and down interfering with its operation. What does the gear look like at the bottom of the shaft? Could something have caused the distributor to move up and down with enough force to break the snap ring?

 

[Aeroking]

Re: Engine flatlines/jumps

still here tracking the problem down.

I went to the local street races (sanctioned) and di "fun-run" 1/8 miles. Of course i won each of the races, but i had to lift off at half track.

At the top of second gear (right about where converter locks up, coincidence?) the truck pegs the knock meter and backfire and bucks and shakes. I know it would have to be deotnation otherwise the engine wouldn't go into a seizure. I tuned the knock retard out, so all the sensor does is record knock, it doesnt affect the spark advance.

My datalogs show smooth and steady values upto and through the detonation. Steady MAP, IPW, AFR, batt voltage, TPS, timing, everything is smooth.

Now the strange part. While cruising on the highway at 50mph or so in 3rd, and i go WOT and it kicksdown to 2nd, i get full boost everything is on 100% and the truck runs perfect through 2nd and 3rd gear with no hesitation. But if i takeoff from a stop, it detonates at the top of 2nd.

the truck pretty much acts different everytime i drive it.

 

[WyoSyclone]

Re: Engine flatlines/jumps

Are you running a TCC lockup switch? Almost sounds like TC problem rather than tune. Can you email a log and BIN from one of those runs??

 

[Aeroking]

Re: Engine flatlines/jumps

fixed one problem, another arose.

my most recent problem of knocking in 2nd gear, did end up being the converter locking up. It set off the knock sensor when it locked up, which jarred the engine by pulling all the timing out.

I ran it the last couple of days and locked the converter low in 2nd gear, and left it locked. and it didnt knock.

New problem. I was datalogging yesterday and noticed my truck was going lean in high boost. Completely different from how its been running. The meth pump is dead. Its getting good voltage, and the line is clean and not plugged. The pump doesnt turn on. So a new one is coming.

Tune in next time as the saga continues.

 

[WyoSyclone]

Re: Engine flatlines/jumps

fixed one problem, another arose.

my most recent problem of knocking in 2nd gear, did end up being the converter locking up. It set off the knock sensor when it locked up, which jarred the engine by pulling all the timing out.

I ran it the last couple of days and locked the converter low in 2nd gear, and left it locked. and it didnt knock.

New problem. I was datalogging yesterday and noticed my truck was going lean in high boost. Completely different from how its been running. The meth pump is dead. Its getting good voltage, and the line is clean and not plugged. The pump doesnt turn on. So a new one is coming.

Tune in next time as the saga continues.

Hey Brandon, from looking at your BIN I suspected it would do that... do you have another log you can send over with it not knocking? We need to move those VE values up in the upper rpm/ve section of your f29x.

 

[Aeroking]

Re: Engine flatlines/jumps

random update:

truck is running great. My spoolup problem is caused by a wrong converter stall speed. My top end RPM problems stem from spark blowout. .022 wasnt good enough, i had to pull them tighter for 20psi and meth.

Right now i am playing with the wastegate duty cycle parameters in $59 to get the truck to hold stable boost.

 

[Beavis]

Re: Engine flatlines/jumps

So it's finally solved?

 

[Aeroking]

Re: Engine flatlines/jumps

So it's finally solved?

yep, it'll be 100% for homecoming 2014

 

[Quickstop [UK]]

Re: Engine flatlines/jumps

.022 for 20psi and meth and it blows out?

Jesus - seems awfully narrow already.

Good job getting where you are. Patience is a virtue!

 

[skwayb]

Re: Engine flatlines/jumps

random update:

Right now i am playing with the wastegate duty cycle parameters in $59 to get the truck to hold stable boost.

If you are using the ECM to control boost here are some tips for getting solid boost with the Stock ECM and Solenoid. By following these steps, I have rock solid boost on a PTE6776 (67 mm dual ball bearing turbo) on the stock ECM/Solenoid setup.

Boost/wastegate tuning Tips

• First Set the Desired Boost -vs- RPM and MPH (F70_MPH) to the PSI you are trying to hit across the board. (i.e. 16psi in every cell)
• Next turn any wastegate POSITIVE adjustments off
  • Positive Step Adjustment to Wastegate (KDCSTEP) set to 0
  • Closed Loop Wastegate Update - Positive Adjustment (KDCTIM8P) set to 0.0 seconds
  • LEAVE the NEGATIVE adjustments ALONE so if you overboost, it will back off the boost.
• Next set the F71 (Wastegate Duty Cycle -vs- MPH) to 0% and make a run. This will let you see what your base boost on the spring is going to be.
• Next set the F71 table to 10% across the board and make a run, then 20%, 30%,etc. This will let you see what % of wastegate will add x amount of boost. This will help you later when you want to run a different PSI, you will know how much Wastegate to add or subtract to hit your PSI goal.
• Do this until you get the wastegate dialed into hitting your target boost you set in the F70 table. Make notes of any spot where you overboost at a shift. You will want to adjust your wastegate down at these MPH spots in the F71 table where it occurs to stop the overboost from happening.

You want to get the F71 MPH (Wastegate Duty Cycle -vs- MPH) Wastegate % as close as possible to running the boost you want from the F70 MPH Desired Boost Table. Make sure there are no boost spikes at different MPHs when your shifts occur.

Once you have the base wastegate dialed in, you can turn this back on.
Positive Step Adjustment to Wastegate (KDCSTEP) set to 1.5-2% to start.
Closed Loop Wastegate Update - Positive Adjustment (KDCTIM8P) set to 0.5 - How often to update the wastegate if not reaching the target boost

This last settiing is one of the MOST IMPORTANT STEPS for getting SOLID Boost control. Slowing the change rate at which the wastegate is being updated to (Closed Loop Wastegate Update - Positive Adjustment (KDCTIM8P)) will let you creap up onto your boost if your initial wastegate F71 setting didn't hit your F70 boost PSI Target. Stock it is set to update 10 times a second (0.1). Change it to 0.5 so it only updates the wastegate twice a second. By doing this, it will stop your boost from fluctating all over the place.

For Overboost control I usually set these 2 items high.

• Negative Step Adjustment to Wastegate (KDCSTEN) set to 3-5% - Back the wastegate off alot
• Closed Loop Wastegate Update - Negative Adjustment (KDCTIM8N) - Set to 0.1 so it backs the wastegate off quickly. (10 times a second)

Those steps should get you solid boost. Like I said above, I have rock solid boost on a PTE67 turbo on a stock ECM/Solenoid control on a stock motor.

Now if you need to change your SPOOL UP behavior, that is another post..

 

[Aeroking]

Re: Engine flatlines/jumps

:tup: thanks Paul.

I've been running straight off the F71_mph with my step adjustments set to 0. I will start playing with the pos/neg steps. And i use the F71_mph to keep boost at minimum (spring pressure) for 0mph-10mph for controlled boost launches. :tup:

.022 for 20psi and meth and it blows out?

I am into the high teens on the gap now

 

[Aeroking]

Re: Engine flatlines/jumps

Welcome to a new season of "This Old Truck". Posting my trial & error in getting my truck to work again.

My 2012 season so far...

My insurance became active April 1st. Up until then i've run my truck twice a week, letting it warm up and driving it around the garage. Everything worked great. I parked it the night before April 1st. Went to take it for a ride the next day, and Code 42. I did not touch anything between it running fine and the error code. Checked with a timing light, and the truck isnt getting any advance. DM connects fine, and shows the ECM is sending a spark advance signal.

So... Things tested to clear code:
- 3 ignition modules (Accel, AC Delco, BWD)
- 3 distributors (stock, billet, reman (new with new module & pickup))
- 2 ECMs, known to be good.
- 6 chips, new bin burns, and old burns
- stock prom
- 2 coils, stock and MSD
- unplugged 6AL, and plugged in
- ECM gets 12+ volts
- good grounds
- pin-out to tan/blk plug - checks out
- tan/blk plug to ign module plug - checks out
- verified knock sensor still connected


Also, a funny occurence. When i turn the truck to on, typically, the fuel pumps kick on and prime the system. I have a racetronix harness, but it still uses the stock fuel pump relay to trigger it. With the truck turned to on, the fuel pump relay opens, and closes once every second.The pumps remain running. When the relay closes, my tach jumps from 0rpm, to 500rpm, then back when it opens. Every second.

My next step will be to cut the 4-pin module plug off, and put on a longer pigtail with a new plug. My stock one pulls the wires pretty tight at the plug.

My truck usually only lets me down when i need to use it. I have no where to go this weekend, so it should work itself out by then. :tup:

 

[Aeroking]

Re: Engine flatlines/jumps

FIXED. Sort of.

I ohmed the tan-black wire before and it was good. Tonight i ohmed it between the dist and ECM (with the disconnect plug), and i got nothing. Tracked it down to the disconnect plug under the kickpanel. Makes sense, truck ran fine until i put the kick panels back in. Did this multiple times. So i cut the connector out, and put a new spade one on. Problem solved.

The sort of...

I put the distributor back together, cranked it over, and nothing. Checked the coil, its putting out nothing. Pulled the cap off, and the reluctor had hit the pickup wire, sliced it. So now i'm gonna order another MSD pickup and see if it runs. cross my fingers.

 

[Aeroking]

Re: Engine flatlines/jumps

digging up the dead version 2.0

Experiencing similar problem again. Since the original problem most things have been swapped out.

- FAST ecm with new harness instead of factory ECM & stock harness
- new coil, new dizzy, new wires
- new injectors & new fuel pump
- new 9/11 converter & refreshed trans
- new turbo & intercooler

Problem now exists at 5300 in 3rd gear. The problem is i get to 5300rpm in 3rd and the rpms flatline at 5300. I have my shift points governed at 5650. When i go to the track the 2-3 is perfect and crisp at 5650, then in 3rd the engine gets to 5300 and levels off. I think it might be converter slip since my speed is 112mph at 5300. Which comes out to like 5% slip. I am not sure what percentage slip should be with a locked converter. I found my hydroboost doesnt return the brake pedal to stock position. Which would activate the lockup switch. So i added a spacer to the pedal to engage the switch when the pedal returns to its resting position. Not sure if it will work or not, havent been to the track since.

If it is the converter not locking, then wouldn't the RPMs continue to climb slipping the converter? My datalogs show i hit 5300 8 seconds into the run and hold 5300 until the finish. I run a lockup switch and flip it halfway through 3rd gear

If the engine winds out to 5650 at full boost in 2nd gear, then it shouldn't be engine or boost related. It could possibly be the lack of timing up top. I only have 17deg in it at high rpm with 110oct. Although last year i had 22deg running 93+alky.

The trans is a race-prep package from a pro builder. I had it refreshed 2 years ago and the builder said everything looked 100% inside. The converter is a brand new (2 years ago) 9/11 2800.

Any suggestions? I have a track rental this sunday and i have a goal that i can reach, but only if i get this sorted out.

 

[BMFB]

Re: Engine flatlines/jumps

Wouldn't 5300 be halfway through 3rd gear?

 

[BMFB]

Re: Engine flatlines/jumps

Side note/conversation.

I think that's really late to lock a converter. It would be easier on the converter to lock it in the middle of second gear. I lock mine at 45 mph. This gives the clutch a less stressful environment in which to engage. Do you log your mph during the run? Does the truck continue to accelerate linearly with relation to the rest of the run or does it drop off steeply?

 

[Aeroking]

Re: Engine flatlines/jumps

i dont log mph. i get that from the trap speed. the speedometer does hover around 110, do i believe i am hitting "terminal velocity" early

 

[BMFB]

Re: Engine flatlines/jumps

well start logging it. If you can see that the engine rpm decreses but your mph continues to increase you will know where you issues are. If the opposite happens you will know its something in the engine tuning. Those chips can be weird...what all are you logging?

 

[Aeroking]

Re: Engine flatlines/jumps

well start logging it. If you can see that the engine rpm decreses but your mph continues to increase you will know where you issues are. If the opposite happens you will know its something in the engine tuning. Those chips can be weird...what all are you logging?

its not a chip is a flash ECM. I log rpm, map, O2 correction, target WB, actual WB, duty cycle, IAT, water temp, knock ret, spark adv, TPS, & AE. I cannot log speed, that would be too easy. :lol: