One last shot... Breaking up!

BoostedSUV

Active member
Re: One last shot... Breaking up!

Dude, quit bein a puss and drive that bitch to work:lol:

Lol! I totally would have if I wasn't too damn lazy to move my dads car out from behind this morning! Plus I still have the interior apart from chasing wires around. I will drive it tonight, put it back together and if all is well there's a good chance I will take it to work and get some laptop time with it. :tup:


And quickstop... Don't think the thought of putting the old injectors back in just to see hasn't crossed my mind. I would like to prove with out a doubt that they're the issue. If they are I'm throwing them away, I can't possibly sell a headache to someone else!!
 

Quickstop [UK]

Combating adversyty.
Re: One last shot... Breaking up!

OK...did some research along what I was thinking and may have something.

Injectors that discharege with high z will be low current, high voltage devices.

You get a massive voltage spike across the injector coils which is transmitted to EM interference (RFI).

This will be most pronounced at specific RPMs wherer the inductance and voltage combine to produce specific harmonics.

Those harmonics would manifest themselves at different RPMs and affect the ignition timing.

Different injectors will have different shielding to suppress the RFI or the coils have different qualities.

The lower the impedance, the higher the voltage on discharge and more interference you may get depending on some other variables.

Maybe..........
 

WyoSyclone

Active member
Re: One last shot... Breaking up!

What I see in P4 is that when the ECM goes into 'Quasi-Asynchronous Fuel Delivery' mode it will "cause the fuel injectors to be energized every other reference pulse, but for twice the duration" - this is a true RPM-based calculation. QAFD is used when the synchronous base pulse width becomes so small that the fuel pulses cannot be accurately delivered - this would correlate to Matt's problem being present when just revving the motor in park or neutral.

I guess if the 50's are very non-linear, not able to deliver their metered spray accurately, or have a mechanical issue (coil breakdown, etc.), it could be a cause for them creating this problem.... I'm just hypothesizing from reading P4.... I'll be anxious to see what the injector gurus have to say.... Dig are you in here?? :D
 

BoostedSUV

Active member
Re: One last shot... Breaking up!

Well gentleman, looks like I jumped the gun... Didn't even make it 2 miles after warming the truck up before it started breaking up! I was all ready to get gas and get some datalogs so I could begin tuning. I turned right back around with my head down in dismay...

It idled smooth and the RPM's came up great last night but today it was like the ECM re-learned a "flaw" and everything came back. The weird part is seems to be doing it at 2100 and 2700 now instead of 1900 and 2500. So weird!

Another thing that has happened to me in the past, and happened again tonight is the truck went to start up after being warm and it kicked over then it wouldn't start. It just cranked and DM showed the RPMs at 6300 while it was cranking. I had to hold the throttle wide to get it fire and code 42 (EST malfunction) kicked up.When it fired up the truck was running like the EST wire was disconnected and was pig rich. Turned truck off then back on and the CEL was gone and it was back to running "normal".


Guys I think I've Had enough... whatever I'm missing I don't think I'm going to find. TurboJ I guess it's time to "eat your eat hat," when are you coming to get the truck? LOL
 

Syclone #1721

I LOVE 4UM SUPERSTARS
Re: One last shot... Breaking up!

Dude, ive been folowing this thing and I would love to come take a look at your truck but I just am so busy right now I cant but let me run this by ya....I recently installed a new distributor in my SY. It was just a Cardone select replacement but it was complete. Put it in and I swear the same thing that you are getting I was getting so I went out and bought a "performance module" from Accel. Same thing happened... I was so pisssed but I am persistant so I bit the bullet and bought an AC Delco D1943A Ignition module and Ill tell you what....the thing has been a beast ever since. Just a suggestion. May work, may not but Ill tell you this..Ive had the opportunity to tour Mr. Gaskets plants when I trained there to tune Accel DFI and they are not impressive....AT ALL....one of the the things that made me switch it out. Its worth a shot. At this point. I got one from Ebay for $45.
 

BoostedSUV

Active member
Re: One last shot... Breaking up!

Dude, Ive been following this thing and I would love to come take a look at your truck but I just am so busy right now I cant but let me run this by ya....I recently installed a new distributor in my SY. It was just a Cardone select replacement but it was complete. Put it in and I swear the same thing that you are getting I was getting so I went out and bought a "performance module" from Accel. Same thing happened... I was so pisssed but I am persistent so I bit the bullet and bought an AC Delco D1943A Ignition module and Ill tell you what....the thing has been a beast ever since. Just a suggestion. May work, may not but Ill tell you this..Ive had the opportunity to tour Mr. Gaskets plants when I trained there to tune Accel DFI and they are not impressive....AT ALL....one of the the things that made me switch it out. Its worth a shot. At this point. I got one from Ebay for $45.

I put the 'ready to run' MSD billet dist in my truck and it was complete as well. I doubted the ign module was the problem but I tried the ACCEL just to see. Nothing changed. I find it hard to believe I could have 2 "bad" ones.. Maybe just not the right one for a sy/ty? What the heck could be all that different? Anyways, I really wish I hand another set of eyes to look over my truck with me, or even move wires around and see if anything changes. I've just about had it... My truck isn't that nice and if i can't get it to run worth a sh*t that really makes me not want. I'm determined but running out of patience and it's starting to get cold outside!
 

cloneman315

Active member
Re: One last shot... Breaking up!

hhmmmmm give me a break down again of what its doing,and what parts are on it?like msd etc etc
 

WyoSyclone

Active member
Re: One last shot... Breaking up!

Matt, that sucks! I was really hoping that would work for you, even though I had my doubts.

You've got to stick with us, man! Just think of all the things you've eliminated as being the cause!

Okay, so all the stuff you've tried hasn't helped. Let's look at that O2 circuit again...
Have you changed O2 sensors?
Can you take your ECM down, unplug it, take a DVM and check the wires between the O2 and the ECM for resistance, having someone flex every inch of the wire for a break?

I'm going to go back through this thread and read everything again and make a little list... maybe we can create a checklist and just take it one thing at a time....
 

BoostedSUV

Active member
Re: One last shot... Breaking up!

Matt, that sucks! I was really hoping that would work for you, even though I had my doubts.

You've got to stick with us, man! Just think of all the things you've eliminated as being the cause!

Okay, so all the stuff you've tried hasn't helped. Let's look at that O2 circuit again...
Have you changed O2 sensors?
Can you take your ECM down, unplug it, take a DVM and check the wires between the O2 and the ECM for resistance, having someone flex every inch of the wire for a break?

I'm going to go back through this thread and read everything again and make a little list... maybe we can create a checklist and just take it one thing at a time....

Rob I'm trying to stick with it. I'm more determined to fix just because I love a good challenge but this is getting crazy! Luckily everything I have changed so far has been for the better so I'm not upset about anything yet.

I've got another O2 sensor that I took out of the truck when I had this problem a long while ago but I didn't try putting it in. Also the truck will still act up with the O2 disconnected.

I traced every wire with a DVM from the ECM harness to every sensor and I could not find any breaks. Everything zeroed out showing they're making connection. I mean I checked every single wire from the ECM and used a wire diagram to see where they went and tested continuity.
 

Syclone #1721

I LOVE 4UM SUPERSTARS
Re: One last shot... Breaking up!

I put the 'ready to run' MSD billet dist in my truck and it was complete as well. I doubted the ign module was the problem but I tried the ACCEL just to see. Nothing changed. I find it hard to believe I could have 2 "bad" ones.. Maybe just not the right one for a sy/ty? What the heck could be all that different? Anyways, I really wish I hand another set of eyes to look over my truck with me, or even move wires around and see if anything changes. I've just about had it... My truck isn't that nice and if i can't get it to run worth a sh*t that really makes me not want. I'm determined but running out of patience and it's starting to get cold outside!

Whats your schedule like? Maybe I could come over next weekend
 

BoostedSUV

Active member
Re: One last shot... Breaking up!

Whats your schedule like? Maybe I could come over next weekend

Next weekend I will be at Atco Raceway for the weekend... The sunday after Halloween will be the next free day I can maybe make available, and that's a big maybe.
 

BoostedSUV

Active member
Re: One last shot... Breaking up!

I just tried running the truck with the O2 disconected to make sure I wasn't getting a false signal to ECM. I don't get any CEL after 10 mins, truck stays in 'Open Loop' and the O2 mV stay around 457. When I bring the RPMs up the truck still breaks up but the O2 mV don't move so I don't appear to be getting a false O2 signal so it would appear that the O2 circuit is functioning.....
 

turboj91

New member
Re: One last shot... Breaking up!

Been crazy busy but just read to bring myself up to speed. Guess I'll keep walking right past the podium and over to the dually. Do you have a preference between the truck being in an enclosed or on an open trailer. PM me your address and I'll make arrangements to come pick up the truck.
 

Syclone #1721

I LOVE 4UM SUPERSTARS
Re: One last shot... Breaking up!

Next weekend I will be at Atco Raceway for the weekend... The sunday after Halloween will be the next free day I can maybe make available, and that's a big maybe.

What day u gonna be at ATCO...maybe Ill come down just to say hey....im 12 miles from Atco...go there alot.
 

BoostedSUV

Active member
Re: One last shot... Breaking up!

What day u gonna be at ATCO...maybe Ill come down just to say hey....im 12 miles from Atco...go there alot.

I figured you were close by Atco, I will be there sat and sun the 24th and 25th. They have 3 $5,000 to win races so I will be there with my and my fathers dragsters. Stop on by!
 

BoostedSUV

Active member
Re: One last shot... Breaking up!

Been crazy busy but just read to bring myself up to speed. Guess I'll keep walking right past the podium and over to the dually. Do you have a preference between the truck being in an enclosed or on an open trailer. PM me your address and I'll make arrangements to come pick up the truck.

Damn it J, I thought that was going to get it! I was just kidding about picking up the truck by the way. lol
 
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