Live Data analysis

AbnMike

Well-known member
Apr 6, 2016
1,218
117
Western Slope, CO
Called a few shops and none had a smoke tester.

In the interim I blew an entire cigar worth of smoke into it. Saw nothing.

Maybe the manifold to exhaust is sucking air? I replaced those gaskets but I wish they used a solid ring instead of that flimsy gasket. I'm going to try wrapping it with exhaust tape and see if the numbers change.

Fuel pressure is at 29/30 when idle and throttle.
 

discostew

Well-known member
Sep 14, 2010
7,706
1,015
Northern Illinois
Called a few shops and none had a smoke tester.

In the interim I blew an entire cigar worth of smoke into it. Saw nothing.

Maybe the manifold to exhaust is sucking air? I replaced those gaskets but I wish they used a solid ring instead of that flimsy gasket. I'm going to try wrapping it with exhaust tape and see if the numbers change.

Fuel pressure is at 29/30 when idle and throttle.

I think that's a little low for fuel psi. Tape that gauge to the windshield so you can watch it and see if the pressure kind of falls off when your driving.
 

AbnMike

Well-known member
Apr 6, 2016
1,218
117
Western Slope, CO
I think that's a little low for fuel psi. Tape that gauge to the windshield so you can watch it and see if the pressure kind of falls off when your driving.

Looks like it should be at 36 so I'll order a fuel pump. No idea when or if the original was changed out and it seems like it runs for a bit longer than it should with the key on to prime it.
 

WaltNYC

Well-known member
Mar 3, 2010
707
135
NYC
Search the site for threads about inexpensive (cheap) replacements for the fuel pump. Global 3270 or something of the sort. ~$25
 

AbnMike

Well-known member
Apr 6, 2016
1,218
117
Western Slope, CO
Search the site for threads about inexpensive (cheap) replacements for the fuel pump. Global 3270 or something of the sort. ~$25

Lucky8 shows the complete kit with seals and whatnot for about $75...seems like a good deal!

Thanks!

The pump runs for about 10 seconds when the key is turned on. It pumped up to 29 without the engine on. I have the pressure gauge sitting on it now to see if it drops any.
 
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AbnMike

Well-known member
Apr 6, 2016
1,218
117
Western Slope, CO
For posterity's sake: Prior to new fuel pump and filter: 14.7 Long Term Fuel Trim.

New fuel pump and new fuel filter:

Last week was running 5.5 Long term Fuel Trim. This week is running 4.7 Long Term Fuel Trim.

Or maybe that's reversed, not sure. One of the two.
 

AbnMike

Well-known member
Apr 6, 2016
1,218
117
Western Slope, CO
Weird. My OBDIi scan tool is showing IAT (F) 124, up from 77 when I started the truck, but they said my charged air temp, or IAT, was -36.

Looks to me like it's working. Maybe they read a stored value or some other sensor? They pointed to the one at the air box.

However it's now showing 133F and outside temp is 63 and I'm running a snorkel pulling fresh air. Not sure how it's getting to 135F between the snorkel and air box.
 

robertf

Well-known member
Jan 22, 2006
4,781
358
-
That's normal.


unplugged is probably a sampling value of 0. 0 probably correlates to -36
 

AbnMike

Well-known member
Apr 6, 2016
1,218
117
Western Slope, CO
Found this note:

MAF reading at 1.74 GPS, should be between 3 and 4


-- that's not going to kill MPG and give me all the other issues is it?

Still not sure why they say my Charged Air Temp Sensor is -36 degrees but my scan tool shows IAT at the proper temperature....
 

AbnMike

Well-known member
Apr 6, 2016
1,218
117
Western Slope, CO
I'm at a loss:

Threw two P1316 Excessive Emissions Faults on start up this morning. I had added Techron fuel system cleaner on Friday afternoon, ran it a bit, then it has been parked for two days.
 

AbnMike

Well-known member
Apr 6, 2016
1,218
117
Western Slope, CO
Just to keep information flowing:

used MAF from Will T and a Charged Air Intake sensor (though I do believe mine was working) and my LTFT came down to 2.3% today. That's the lowest it has ever been.
 

AbnMike

Well-known member
Apr 6, 2016
1,218
117
Western Slope, CO
Another follow up:

90 degree day, city driving - ran a can of Seafoam in the gas tank and one is running through the oil/engine right now in prep for an oil change:

LTFT 0.8

I'm guessing that's about as perfect as a truck with 178,000 miles on it can get.
 

WaltNYC

Well-known member
Mar 3, 2010
707
135
NYC
He sold it on Bring a Trailer. For real. Got very good money for too.

 

4Runner

Well-known member
May 24, 2007
660
110
Boise Idaho
It’s been a bit since messing with a GEMS unit but it seems weird that your in closed loop mode, 842rpm and yet your at 30 degrees of advance. I also think there is a vacuum leak somewhere for a start. I had 2” of lift and 245/75/16’s on a well worn platform and would get 12 to 14mpg’s. At the risk of starting a new debate, I would say that lower intake air temps are better to a point but there are losses from having to pull the air thru the extra length of a snorkel. Just guessing that nobody is getting RAM air benefits from snorkels, just cleaner air.