Stall Question

jconna · #1 Mon, February 8th, 2010, 03:31 PM

I've been noticing a miss (especially in low RPM and most noticible in reverse) since I installed my Gryphon. Figured I'd give it a bit but it actually stalled out on me today backing into a parking spot. Running level 2 tow. Any ideas?

***88Racing*** · #2 Mon, February 8th, 2010, 04:13 PM

Year of truck?
Engine?
Miles?
Last time sparkplugs/COP changed?

jconna · #3 Mon, February 8th, 2010, 06:09 PM

2004 5.4. Might as well say 70,000 on original plugs. Don't know what COP means.

JWBFX4 · #4 Mon, February 8th, 2010, 09:22 PM

Quote:

Originally Posted by jconna

2004 5.4. Might as well say 70,000 on original plugs. Don't know what COP means.

COP= coil on plug

Does the miss happen all the time or is it more sporadic?

***88Racing*** · #5 Mon, February 8th, 2010, 10:43 PM

Coul be a variety of things causing this.
Throttle body needs to be cleaned.
Mass air flow needs to be cleaned with MAF cleaner.
Low grade miss fire from plugs or COPs.
When canned level 2 tow was loaded did you notice a difference in idle when warmed up?

jconna · #6 Mon, February 8th, 2010, 11:33 PM

The first time I noticed it was backing into my parking spot at work the day after I installed my unit. This was 4 days ago and it's happened in the same scenerio each day since but today to the point of a stall. Not sure what to make of it.

As for idle.....Idle's high on start up 1300 or so and then drops down to around 600. It's habit that I never pull out before the idle down and I can't say I notice much difference now vs. before I installed the programmer. Seems to take about the same timeframe and drops to around the same level. If anything....RPM's may baseline a little higher than before. It used to drop to around 500 before I pulled out. Once warmed up.....It appears to run around 700 now which does seem higher than before. I believe even once warmed up before installing the programmer it would still hang around the 500 mark but I can't promise my memory is serving me correctly on that. Overall in answer to your question....It apears to run a little higher RPM at idle across the board.

The possible issues you are mentioning make sense as to the possible cause of the issue but I don't get why they never occurred before I installed the gryphon. All I can figure is that it modified settings based on the assumption that everything was in good working order when in fact I do have an issue with one of the mentioned. Overall I'm happy....Much better acceleration and shifting....This stalling issue has me a little concerned though. Something that is going to drive me crazy until I figure it out.

***88Racing*** · #7 Tue, February 9th, 2010, 12:15 AM

Sometimes programmers amplify certain things such as dirty throttle bodies and or MAF's. Just the nature of the beast I guess?!

You need to fill out more of your user cp like HEX and serial number also.

***Jackpine*** · #8 Tue, February 9th, 2010, 12:27 PM

Quote:

Originally Posted by jconna

The first time I noticed it was backing into my parking spot at work the day after I installed my unit. This was 4 days ago and it's happened in the same scenerio each day since but today to the point of a stall. Not sure what to make of it.

As for idle.....Idle's high on start up 1300 or so and then drops down to around 600. It's habit that I never pull out before the idle down and I can't say I notice much difference now vs. before I installed the programmer. Seems to take about the same timeframe and drops to around the same level. If anything....RPM's may baseline a little higher than before. It used to drop to around 500 before I pulled out. Once warmed up.....It appears to run around 700 now which does seem higher than before. I believe even once warmed up before installing the programmer it would still hang around the 500 mark but I can't promise my memory is serving me correctly on that. Overall in answer to your question....It apears to run a little higher RPM at idle across the board.

The possible issues you are mentioning make sense as to the possible cause of the issue but I don't get why they never occurred before I installed the gryphon. All I can figure is that it modified settings based on the assumption that everything was in good working order when in fact I do have an issue with one of the mentioned. Overall I'm happy....Much better acceleration and shifting....This stalling issue has me a little concerned though. Something that is going to drive me crazy until I figure it out.

I'll try to answer your question here. The "learning" capability of the PCM allows it to cope with gradually changing conditions as the engine ages. It compensates for things like partially clogged throttle bodies and similar issues.

When you load a custom tune though, all that "learning" is wiped out, because the tune is written for a "perfect" system (you couldn't really write the tune any other way - nor would you want to). Now, the PCM can't learn fast enough to compensate for what it sees as a sudden change in component operation and the truck can run badly. I'd take a peek at the throttle body if I were you and probably look at the MAF sensor too. Here's a link to a thread on cleaning the MAF sensor: How to Clean MAF-2005 5.4 - F150online Forums It should be valid for your truck too.

- Jack

jconna · #9 Tue, February 9th, 2010, 09:55 PM

I updated my CP with the information I know...Will need to pull the S/N tomorrow. Thanks all for the input! I'll try and pull the throttle body and MAF sensor off for a good cleaning as soon as I can get the chance and see where it leaves me.

***Jackpine*** · #10 Wed, February 10th, 2010, 12:44 PM

Quote:

Originally Posted by jconna

I updated my CP with the information I know...Will need to pull the S/N tomorrow. Thanks all for the input! I'll try and pull the throttle body and MAF sensor off for a good cleaning as soon as I can get the chance and see where it leaves me.

The S/N should be your "Invoice Number". However, you can verify this through the diagnostics menu.

- Jack