Just went out to check some maf transfer changes I made in my tune. A/F 11.6-11.7 through second gear. Hit third at wot and the engine died. No funny noises, no warning. Acted just like when I had a bad chip in the truck. I tried to re-start and it didn't. Tried again and floored it and it fired up and ran fine all the way home.

I don't have a chip in this truck so that's not it. All the electrical worked fine also. Any ideas? Is there something in the computer, some parameter I may have exceeded that shuts the engine off? It did not come close to the rev limit, was running 20 psi and the boost bypass is shut off in the computer.

No codes are set in the computer.

Jody

 

That's strange. The only time I had that happen was a flip chip compatability problem. Reran it on dyno and couldn't figure it out. Switched that chip to a different truck and it worked in that one.


How are you running your tune without a chip? Programmer??

 

Yes, I use the Pro Racer flasher unit. I had the same thing happen with a 4 way chip and it felt exactly the same, but there's no chip now.

Do you know how the rev limiter works on these trucks? I know it shuts the fuel off, but doesn't it turn it back on when the rpms drop to a preset point, or does it keep them off? My shift rpm is 5800 rpms and the limiter was set at 6200 rpms and so it's POSSIBLE that it may have overrun slightly and triggered it. I've since moved the limiter up to 6500 rpms but I really want to know what the hell happened!

As far as not re-starting I'm thinking that was due to being flooded as when it shut off I still had my foot in it and as the truck slowed I was trying to keep it running. The engine was turning over since the converter was locked and I'm guessing with the throttle being held open some it kept pulsing the injectors, flooding the engine. It re-started when I floored it to clear the excess fuel.



Jody

 

Well when I banged the rev limiter heating up slicks at the track it never shut off.

And in my cobra I hit the rev limiter alot. It just stutters. I don't think that's your problem.
I agree with the flooding part.

The only reason I can come up with is a programming problem.

Let me know what happens. I can ask a friend that owns his own ford performance shop if you want

 

Thanks Dave. My confusion regarding the rev limiter is that doing a search on the boards I've found some people claiming the truck has shut off just like mine when it hit the limiter. Others say it doesn't.

Jody

 

I've got a bad tune right now, but a few times the L would not get out of second for almost a second and 2 days ago I floored it at 110 mph and it down shifted to third and went limp. No throttle just a bad coast. I put it in neutral and restarted it and it was OK after that. Weird! Oh, I have a Revolution chip.
Thanks for the info on JLP's KB intake sale price.

 

Where did you get that Pro Racer flasher unit? I have a Maf extender ( not installed yet ), soon to have a JLP KB intake , and I was going to get a dyno tune on the Revolution chip, but if this Pro Racer flasher unit is better I need to know! Thanks

 

Ive had mine shut OFF just like yours.

 

Well it's better only if you want to be able to do your own tuning. They give you a start-up file which for me was as close as my previous custom tunes, and then you tune from there. With the Pro Racer you are the tuner, EVERYTHING is available to you for modding.

I got mine here:

Modular Depot

Jody

 

Thanks! I raised the limiter, it was about 400 rpms above the shift rpm, now it's 600 rpms above. By the way, I'm dying to know how you know where my truck goes into OD at (from a previous post from you to me!).

Jody

 

Thanks!

 

I think Steve was just trying to offer a suggestion to your problem.... No need to get your panties in a bunch..

I suppose he'll be less likely to help out next time...

-Dale

*edit*
The only reason my truck has died has been when the chip came loose or when the headgaskets popped and the motor ingested coolant.. Ive banged off the limiter quite a few times (Most of the time on the 1-2shift) and the truck has never died... If that helps ya any....
*/edit*

 

I used the Vulcan Mind meld.

I didn't know. I didn't know you were talking about WOT. I gave you a suggestion for partial throttle detonation in OD, which is common and I assumed you had. You didn't say @ WOT in your original post.

I don't care when you shift into OD cuz you will be behind me at that time.

 

Dale and Steve,

I worded it as carefully as possible but it was still misunderstood. I did NOT mean it as a smart-*** comment, not my style at all. I thought my original post said it shut off going into third gear at WOT but I'll re-read it in a second.

The reason I was asking is because he is in my area and I thought maybe we knew someone in common who'd said that. It wasn't a slam to him at all! I didn't think you'd interprete it that way.

No, the truck doesn't ping going into OD at normal driving, I have it set to not go in until 55 mph or so.

 

That is very possible. Looking for 600+ rwhp on the race side and about where you are on the street tune. And I'm way behind you in the race curve as the truck has seen very little track time.

Jody