Surging...help!

whateverz · #1 (**permalink**) 06-23-2007, 04:05 PM

Ok, I posted this a year or so ago and never figured it out so here it goes again.

Under load and mostly at steady throttle my truck surges in about 1 sec intervals (power on/ power off). You can't really see it in the tach, but it is very pronounced by the seat of you pants. Mostly in the low to mid 2k'sand under a load, the more load the greater the surge. For the last year I have tried doing things here and there but mostly just dealing with it. Untill i got fed up this week and drove my ECU back up to Jet Performance to have them reflash it. I have taken out the iridum plugs and went back to stock. I have cleaned the MAF sensor and throttle body, changed the fuel filter, and pcv. Serviced the tranny (cleaned the filter) to eliminate that posibility. And the only thing left is the Jet chip. When I explained what its doing to them, they said it shouldn't be the programming, it would be running rich or lean, if there was a problem. And said it sounds like a bad coil pack. I came back threw it back in and it's still doing it. So most likley, not the programming.

So my question is, does this sound right? Has anyone experienced this? What happens when one of the coil packs goes out, and when do they usually? I might just get one of the proscan tools, but might wait till my friend (experienced mech is out of town) returns. He thought it was the programming too. So any ehlp would be great, somtimes a bit of experience is worth a lot of time and money. It might be a "so obvious, it's invisible" thing. Thanks.

whateverz · #2 (**permalink**) 06-23-2007, 04:47 PM

I think I finally found my problem in this thread, one thing that wasn't done. http://www.tundrasolutions.com/forum...g-1999-solara/
I will try on Monday. Thanks guys.

beboff · #3 (**permalink**) 06-24-2007, 04:46 PM

Quote:

Originally Posted by whateverz

I think I finally found my problem in this thread, one thing that wasn't done. http://www.tundrasolutions.com/forum...g-1999-solara/
I will try on Monday. Thanks guys.

Mine 2001 tundra has been doing it to for some time.Where is the EGR position sensor on the v8 tundra?

mustang67408 · #4 (**permalink**) 06-26-2007, 03:13 AM

Tundras do NOT have EGR's.

A bad coil pack should set the engine light and/or set a code.

I would also loose the Jet Chip.

Have someone read the codes, they can be "pending" and not set the engine light.

Low fuel pressure will make a vehicle surge and not set a code or engine light. (2000 tundras are known for this)
Dirty fuel filter from a tank of bad fuel or dirty fuel.
CHECK FUEL PRESSURE
Clean the MAF sensor might help

Try dropping the exhaust before the cats, they might be plugging up.

beboff · #5 (**permalink**) 06-26-2007, 02:04 PM

Quote:

Originally Posted by mustang67408

Tundras do NOT have EGR's.

A bad coil pack should set the engine light and/or set a code.

I would also loose the Jet Chip.

Have someone read the codes, they can be "pending" and not set the engine light.

Low fuel pressure will make a vehicle surge and not set a code or engine light. (2000 tundras are known for this)
Dirty fuel filter from a tank of bad fuel or dirty fuel.

Clean the MAF sensor might help

Try dropping the exhaust before the cats, they might be plugging up.

THANKS!!!!!!! I Will try that!

whateverz · #6 (**permalink**) 06-26-2007, 02:36 PM

Just had it checked and it is throwing no codes. He said the O2 sensors were not reacting as fast as they should (lazy). and we were noticing that the Downey headers have the O2 mount bung off to the side and not directly in the flow. But this problem was not evident directly after the header upgrade. He thought fuel pressure too, cause flow was registering good when it was started. He recomended tapping the fuel rail to get a pressure read.

Is this how it's done? What is the correct procedure? Little leary of tapping my fuel rail.

The fuel pump makes total sense. Cause it's only when it needs lots of fuel. I replaced my sending unit and didn't spring for the pump like a jacka!@. There was lots of magnetic particles, and I tried to clean it up as well as possible. BTW, it was doing this before messing with the sending unit. And the tank strap bolt got stripped and I had to re-tap new ones due to tank damage. So I am not looking forward to dropping the tank again.

Don't the pumps just go when they are bad? Or can it be a slow degrade? What about a Walbro?

And next time I am up in Huntington Beach I will bring my ECU and have Jet flash it back to stock. I don't have much faith in them.

beboff · #7 (**permalink**) 06-26-2007, 05:44 PM

Quote:

Originally Posted by whateverz

Just had it checked and it is throwing no codes. He said the O2 sensors were not reacting as fast as they should (lazy). and we were noticing that the Downey headers have the O2 mount bung off to the side and not directly in the flow. But this problem was not evident directly after the header upgrade. He thought fuel pressure too, cause flow was registering good when it was started. He recomended tapping the fuel rail to get a pressure read.

Is this how it's done? What is the correct procedure? Little leary of tapping my fuel rail.

The fuel pump makes total sense. Cause it's only when it needs lots of fuel. I replaced my sending unit and didn't spring for the pump like a jacka!@. There was lots of magnetic particles, and I tried to clean it up as well as possible. BTW, it was doing this before messing with the sending unit. And the tank strap bolt got stripped and I had to re-tap new ones due to tank damage. So I am not looking forward to dropping the tank again.

Don't the pumps just go when they are bad? Or can it be a slow degrade? What about a Walbro?

And next time I am up in Huntington Beach I will bring my ECU and have Jet flash it back to stock. I don't have much faith in them.

If you find the problem let me know.

whateverz · #8 (**permalink**) 06-26-2007, 05:54 PM

Quote:

Originally Posted by beboff

If you find the problem let me know.

Will do.

Does anyone know the right way to check fuel pressure?

beboff · #9 (**permalink**) 06-26-2007, 07:19 PM

Quote:

Originally Posted by whateverz

Will do.

Does anyone know the right way to check fuel pressure?

I have no idea. My mechanic drove my truck the other day and he also felt the surging. He ask me to bring it back to him to keep all day that way he will go over the whole truck starting with fuel and fuel pressure. I will let you know.

mustang67408 · #10 (**permalink**) 06-26-2007, 10:04 PM

Checking fuel pressure (see attachment)

Lots of particles in the fuel tank is bad....
Definatley change fuel filter

Damaged tank???? How bad???
Is the fuel pump submerged completley all the time, or does it sit on a dent, which woul move it up and out of the fuel.

Did you get the little hose back on the pump properly when you changed the sending unit. I have seen that hose bleed fuel pressure under load because it wasnt totally secured upin reassembly. (don't ask me how I know) LOL

whateverz · #11 (**permalink**) 06-27-2007, 12:50 AM

The old tanks damage was nowhere near the unit. It is a brand new tank been in for a year now and I am pretty confident on the reassembly. I have changed the fuel filter 2 times, and it just changes, not elimanates the problem. I blew off the magnetic particles on the pump when I changed it, but again did not change anything.

It is so consistent it seems electronic. If you are going up a hill around 2k-2300 rpm it is one second intervals. One full power, one low power, etc.

If you turn a corner uphill and punch it it goes, then delays hard for a second, then full power till its in the 2's. That is the most sporatic it gets.

I am going to Mex for a a couple days, and my mechanic gets back on sunday. So I will see if he will test pressure then. I am real close to telling the dealer to just figure it out. Thanks for all the help, and I will post any findings right away. Hopfully some more good ideas when I check in again.

Picasso · #12 (**permalink**) 06-27-2007, 05:57 AM

Quote:

Originally Posted by whateverz

Will do.

Does anyone know the right way to check fuel pressure?

I used an Actron fuel pressure guage that came with a fuel rail adapter that fits our trucks. Here's a link to the album in my gallery showing a few pics of it being used on my engine.

Paul

mustang67408 · #13 (**permalink**) 06-27-2007, 08:27 AM

Quote:

Originally Posted by Picasso

I used an Actron fuel pressure guage that came with a fuel rail adapter that fits our trucks. Here's a link to the album in my gallery showing a few pics of it being used on my engine.

Paul

Thanks Paul

Hmmmmm, Thanks, for a better explination. I will keep thinking and post any more ideas if I think of any.
Please keep us posted.

whateverz · #14 (**permalink**) 06-27-2007, 11:04 AM

Picasso, Thanks for thr link and the pics. Have to try it out.

whateverz · #15 (**permalink**) 07-06-2007, 10:52 AM

Haven't had a chance to check the pressure. But a family friend (mechanic) had to borrow the truck. He said the O2 sensors were probably the culprit, if not, that is one more possibilty eliminated. Being that they were not reacting that fast, kinda makes sense. So I might try that out and repost. Sure going to ba an expensive one!