2002 low power towing

[Mayhem17]

2002 2500 auto. I've had this truck for about 5 years now, and it's been this way since I've owned it. Honestly wasn't sure if it was just supposed to run like this to be honest. Picked up a new camper this weekend, and had issues keeping it at 65 mph on very slight grades without finally downshifting around 60mph just to hear it scream. Even then it really didn't pull hard. Truck is stock, with a few addons. K&N cold air setup, straight exhaust, and an Edge EZ tuner. I added the tuner a couple weeks after buying the truck, and honestly didn't notice any difference. Truck maybe got 1-2k miles per year. Planning to change that with this camper. Today I tossed on a fuel pressure gauge to see how she did under a load on the stock fuel pump setup. She sits around 12 psi at idle, maybe 13. Driving around normally, around 10-11. WOT at highway 60-70 mph going up a good hill, it was around 3-4. Now, as low as that seems, from what I understand on the stock setup, that's about normal. I pulled and cleaned my MAP and IAT sensors. Both had no change on watching my scanner. My concern though is with the MAP sensor. It's reading 57.6 Hg with just the key on. Which is 28.3 psi, minus 14.4 is 14.3 psi of boost not running. It's slightly higher when idling, but barely. At WOT it reads 75 Hg, which is 36.8 psi, minus 14.4 is 22.4psi. There was no change with or without the Edge EZ installed. I figure I have a bad MAP sensor, judging by the readings when the key is on, but would that honestly cause my issue? I honestly was figuring I'd find very low readings from my MAP, which would cause lower fueling even though I'm building boost. Sorry for the long read. Any advice?

 

[Road Dog]

I do a lot of mountain travel and downshift all the time (47RE and 3.55 gears). With my camper I'm at my GVW (11,000#). I try to keep my EGT below 1,200F and downshifting is the way to do it. Typically I'll be going up hills in third at 80-90 km/h (50-55mph) and 2,200 - 2,500 RPM. There's no advantage to running at low RPM.

 

[Bob4x4]

When you added the Edge box did you address the wastegate? With the 02 hy35 turbo you need to modify when the wastegate opens

 

[DavidC]

My 99 was pretty low when stock. After the DTT trans and Edge Comp box I can go up the steep grades at a reasonable speed. When stock it was gutless so unless your ready to do the trans your pretty much stuck.

 

[Mayhem17]

After some testing, I'm pretty sure this Edge EZ doesn't function at all. That being said, I just ordered the new quadzilla setup. That way I'll have the gauges I need also, and can just use the lower tunes for the time being and see if I feel like dumping a ton of money in this old truck to really make it sing.

 

[DavidC]

You will have to let us know your impression of the Quadzilla set up.

 

[Tractorat]

Will an EZ lose power over time ? Mine is about 19 years old and Ive ofter wondered if I should replace it. Is there a way to test it without just unplugging it and going back to stock to see what the diff is ?

 

[DavidC]

Don't know about EZ problems but I have gone through 4 Comps in 20 years. Here's an interesting link on thw quad
https://mopar1973man.com/topic/11848-goodbye-edge-comp-hello-quadzilla-adrenaline/#comments

 

[Road Dog]

It shouldn't since it's electronic but parts of it may fail over time. The only way to know is put the truck on a dyno or find an empty road and do some WOT testing. My Edge Juice has "performance tests" and will measure 0-60 and 1/4 mile times. It also has diagnostic LEDs under the end cap.

 

[Vaughn MacKenzie]

Mayhem, I would replace the MAP sensor. They have certainly been known to go bad on these older trucks. Do the IAT while you're at it. I just bought a new MAP and IAT sensor, not too terribly expensive but a good thing to do every decade or two even not driving a lot of miles.

You may want to upgrade your lift pump at some point. 3-4psi is a little on the low side, but not harmful if you don't keep it there long.

When you have a good load you do want your truck to downshift by 60mph, better to rev it in Drive than lug it in OD. You could run it at 2500-2700 all day long it's not going to hurt it at all.

The Quadzilla was a good choice, plenty of tunability. It's on my wish list!

 

[BigPapa]

I’m going to be that guy......

Ditch the K&N. Nothing but trouble there.

 

[SnoKing]

When I ran the HY-35, I recall having put a spring on the waste gate to keep it from opening getting more boost. The EZ just fools the engine computer so that it does not defuel to decrease higher boost levels. All 2nd gen should have pyro (EGT pre turbo), boost and fuel pressure gauges and autos a trans temp gauge in the transmission output line to the block mounted fluid cooler on the passengers side before the exhaust manifold. If you go back to my post in the 2004 time frame there is a thread about such things. Here it is: https://www.turbodieselregister.com/threads/building-a-2001-5-auto-to-tow-and-stop.114893/

 

[Vaughn MacKenzie]

10-4 on the K&N. That's the only air filter Cummins has mentioned specifically by name to never use.

 

[Mayhem17]

So, the Quadzilla really does the trick. I did replace my MAP sensor, as it was reading like 14 psi when the truck wasn't even running. It's a totally different truck on some of the lowest settings. I did also get the one where I can monitor everything through my Bluetooth device. Was a nice option which didn't make me have to buy a separate set of pillar gauges. I do need to still pick up one of those ''x hooks'' for my HY35 though it seems. From what I understand, that'll make a night and day difference when paired with the tuner also. Should bring it up around 30 psi or so if I understand correctly. I actually haven't had the chance to pull with it yet since I did the install though. Had a list of things I wanted to get fixed on the truck before my big trip in June. I'll try to get back on here with some updates. I'll see what I can do with the K&N though. It had the entire CAI setup when I bought it, so I'd have to replace the whole thing.

 

[BigPapa]

Just an FYI, standard atmospheric pressure at sea level is 14.7psi. If your sensor read “0” you’d have a little trouble breathing.....