Engine/Transmission (1998.5 - 2002) Catchers and half throttle power?????

[BRI7070]

I have had my Catcher for a couple of months and over all I am happy with it, except for one thing. When I am accelerating, if I go to half throttle and back off slightly, about 1/8 travel, I get a surge of power that is about the same as WOT. If I move the loud pedal just a little I lose the surge. This can make the pucker factor HIGH when passing.



I have tried the APPS reset. 30 Min, then 2 HRS ,then over night and still have the problem. so I got to replace the APPS with my brothers and still no better. I even tried the dead APPS I replaced 2 years ago. no luck.



So, Any suggestions?????????

Thanks

Brian

 

[Supermod56]

Strange, I assume you have the Catcher that is compatible with the Comp? Have you tried it w/o the comp on?? I have the "Standard" Catcher, only thing I notice is the motor doesn't like to be lugged down as much, other than that it's great.



Tom

 

[BRI7070]

i started with the Special Catcher for the EDGE Comp and had the problem. So I decided to sell my Edge Comp and go the original version of the catcher thinking I got a bad Flash. However with the original version I still have the problem and I have not installed the TST comp.

 

[RJPotts]

Is there a possibility you need to reset your APPS?

This sounds like a possibility, a very extreme case, but possible.

-R. J.

 

[BRI7070]

As stated in my frist post I have tried the APPS reset several times with different APPS.



Trying to find out what else might effect the catcher

 

[fox]

I am watching this closely because mine does it too.

BUT, it did it with the stock ECM exactly the same. I thought it was the VP. But that is changed out, Catcher is on and still the surge. It does it at different boost levels too. Map is clean. IAT has not been checked yet.

 

[BRI7070]

I did not have this issue with the Stock ECM. Also before I tried my brothers APPS , I did a road test to see if his did it and I could not feel anything. But I could feel it big time in my truck.

So what else effects the fueling on our trucks???????

 

[fox]

This last saturday, I cleaned the IAT sensor, it wasn't bad, then tightened the grounds on the L fender.

It did not surge today!!

I hope it is that simple.

 

[BRI7070]

I( will try that tonight. I also e-mailed Marco. I hope he can provide some input.

 

[BarryG]

I also have noticed this. My catcher has only been on a week or so. It is definitely a bit annoying. However the other benefits more than make up for it. Would be nice to get it cleared up though. If you hear back from Marco please post his response

 

[Marco]

BRI7070,

Just to make sureyou got the right software for your truck...

Your truck is a : 01 / Auto / Fed? With rear drums?



Marco

 

[rivercat]

mine is 02 fed 6 spd with rear disk.



does that make a diffrence I have it too seems to stumble at wot and run best at a sweet spot at half throttle as described above makes it had on the wife to drive it real jerky

 

[BRI7070]

Marco,

Yes mine is an 01 / Auto / Fed . With the rear drums.



With a build date of Jan 2000 would it use the 2000 or the 2001 software?



Brian

 

[BarryG]

Marco:

Glad you responded to this thread.



As Rivercat mentioned it is like a stumble or maybe defueling let off the go pedal just a bit and it comes to life and takes off. It doesnt have to be a wot run. I have been watching the gauges and nothing seems wrong, nothing out of the ordinary. If you hold the go pedal constant and try to drive through it it is like defueling is occurring it just wont build anymore boost and speed is very slow to build. However just let off a bit and it takes off like you would expect.



My catcher had a handwritten note on it or maybe it was on the box that said 01 late auto. Nothing about fed or calif on it. How do you know if you really have the right software?



Mine is an 01. 5, auto, rear disk, fed, build date of nov 2000

 

[Marco]

Sorry, I've been busy yesterday. Since I knew that this MSG would've need to be a longer one, I simply had no time to type it.



With the CaTCHER beyond a certain point of the throttle nothing more seems to happen ( under certain circumstances, I'll come back to that at a later point ).



Why is that? In short and to keep it simple, we've squenched out everything from the VP it can give. If we've reached the VP fuel output limit by let's say half throttle then increasing the throttle further gives... you guessed it, nothing.



Furthermore backing out from WOT a little produces a surge in power. Why is that?



That is the reaction of the high idle torque limiter( Or better known as rev limiter ). The truck does it even in stock form. It's more noticeable at top speed and full power but it IS there stock. The CaTCHER amplifies that surge in a certain sense making it more noticeable. ( Please notice I'm talking about WOT!!! N O T half throttle! )



With a stock file in my truck, if I lay down WOT ( and keep full throttle )the top RPM is around 2800. If I baby the throttle gently and back out a little and then increase again a little and so on, I can get up to 2900-3000 Rpm. That means speeds above 110 Mph. Have you ever tried it? You WILL notice it.



With the CaTCHER in my truck I can get the top speed up to 3300 Rpm, always playing gently with the throttle... That's over 120 Mph with my 33 inch tires. The rev limiter is the beast I've fought with for a long time, never been able to beat him... :{ :{ :{



So why do I tell you all that?

Simply to make you understand how to use the throttle with the CaTCHER. Gently and increasing the throttle accordingly to the speed or better RPM. the result is no dead spots like when you stomp on it and let her go.

Stomping the throttle with the CaTCHER is a no no.



Yet, BRI7070 sez:

"When I am accelerating, if I go to half throttle and back off slightly, about 1/8 travel, I get a surge of power that is about the same as WOT. If I move the loud pedal just a little I lose the surge. "



HALF throttle???



With your experiences, please help me understand.

1)Does it happen at certain speeds/all speeds?

2)In all gears or maybe only in OD?

3)Towing, loaded, unloaded, always?

4) Flat road / hills / mountains / always?

Please give me any detail you can provide!



Thanks,

Marco

On Edit. I've checked, you've got the correct software for your truck. Wrong software is ruled out.

 

[BarryG]

Marco:

I am not br17070 but will give you some of that info and maybe he can verify it as well



With your experiences, please help me understand.



1)Does it happen at certain speeds/all speeds?

it only seems to happen above 35mph that i have noticed but will continue to monitor and see if I can narrow it down more specifically



2)In all gears or maybe only in OD?

Have not noticed it in 1st or 2nd at all. Am checking now to verify if it is only in 3rd or od or both.



3)Towing, loaded, unloaded, always?

Have not towed with it yet but loaded and unloaded yes. Always not sure, it does not do it all the time but hard to say as it may be always if specific conditions are met will continue checking



4) Flat road / hills / mountains / always?

I live in Colorado and drive all those conditions. It has done it in all of those situations



Appreciate your time in thinking about this issue.

 

[Marco]

Thanks for the input! Keep 'em flowing!

Only doing so we can rule out the possible causes.



Marco

 

[BRI7070]

With your experiences, please help me understand.

1)Does it happen at certain speeds/all speeds?



I have noticed it in speeds of 25-105. I have not gone above 105, but i have gotten able to play with it. I would be in the power spot, accelerating like a bat out of he77, then go past it loose power, go back to it like a bat again and so on.



2)In all gears or maybe only in OD?



I have not felt it in frist, but I never tried to make it happen in frist. I will try tonight. But I can make it happen in 2-3-and OD



3)Towing, loaded, unloaded, always?



Always



4) Flat road / hills / mountains / always?

I can find the power spot in any condition.



To further explaion the hale way point...

When driving down the road as I depress the accelerator slowly, there is a point which I can feel more resistance. I have explained this to my tranie man and he told me that it is the point where the spring on the TV cable becomes fully depressed.

It is at that point Where I can back off about 1/8 travel and find the power spot.





"Why is that? In short and to keep it simple, we've squenched out everything from the VP it can give. If we've reached the VP fuel output limit by let's say half throttle then increasing the throttle further gives... you guessed it, nothing. "



As far as WOT, If I slowley depress the go pedel to WOT O can Feel Increase in Power all the way.



The rev limiter is the beast I've fought with for a long time, never been able to beat him...



Is the battle still in progress?

What about the torque limiter on the bottom end?





Marco, Over all I love my Catcher. I thank you for your hard work.



Brian

 

[Walt-L]

I'm glade I caught this post since I have the same problem BRI7070 has. I can always tell the non responsive half throttle when the boost will not increase from 10 or 15 lbs. Then just back out of the throttle just a bit and the boost surges up towards 25 and she's off like a shot, press in on the throttle just a tiny bit and bingo, the boost drops back out! This is running any where between 64 and 75 for the MOST pronounced effect of this glich. I just installed the Bosio RV275 nozzels the other day and they have had a magnifying effect on this problem. I have reset the APPS about 5 times to no avail. I thought I would need to get a new APPS since I thought its happening right where the APPS would have the maximum amount of wear. I will try the plugs and grounds next. I too love what the CaTCHER has done for my truck, but this one gremlin can become quit an annoiance. I can only hope Marco can find a flash that will tune this out IF infact the fix is there. I will be the first to send mine back for the update!

Marco Be Well and Gods Speed!

 

[fox]

I thought cleaning the grounds helped, but it is back and similar to the rest.

Frustrating when passing a car. It goes almost flat , then I lift some throttle to get back in line and it surges ahead and runs good only to repeat again in 2-3 seconds.