My grandparents used to take me to Colorado every summer when I was little so when they told me they were going back I was excited. They left Saturday morning and I left Sunday morning in the 98 12v. Other than a ball joint fiasco, I haven’t had any problems out of this truck and after I put a heater core in a few weeks ago, I thought it was road ready. My scan gauge was acting up halfway through my 13 hour trip but I didn’t think that was much of a problem. I get about two hours from camp and stop for fuel and there is a miss that has never been there before. Egt’s have been running hotter than usual since I got up in the high altitude and it didn’t have as much power as normal but I chalked it up to the altitude. Fast forward yesterday morning and we decided to head to a hamburger joint 15 miles up the mountain. Went to start the truck and it didn’t pop off as usual and in fact did not want to start at all but finally did with a huge cloud of white smoke. So now I’ve got an Injector dripping or something not right. We head up the mountain for a burger on the rough dirt road but before we got halfway there, I noticed my alternator was not charging, so we turned back around. I realized that’s the problem with my scangauge, it wasnt getting the power it needed to run. I headed into Del Norte, about 15 miles down the mountain and luckily Napa had a alternator. Swapped that in the parking lot and all it good with the charging. I hope I can make it back to Texas with this injector issue and not cause any other issues driving it.

I’ve been reading up in this and it seems a lot of people have the exact problem I had. I need to get timing tools and advance it a bit and also new injectors. Truck runs too darn good down here in the low country.

On 7/4/2019 at 10:19 AM, JAG1 said:

So does that mean worn injectors are harder to detect on a VP truck since the ECM can compensate?

 

Pretty easy...

 

A 24v will compensate for altitude well not altitude but the lack of air. It will adjust the fuel air ratio timming everything really. The 12v wont, itl run richer with less air, less dense air at altitude. Itl always push the same timming and fuel unless you physically change it.

 

However the vp and all computer controlled trucks will make more power at sea level because the air is dense more of it. The fuel air mixture there will create more power it's like stuffing more air and fuel into the combustion chamber.

That's why most all hp ratings are done at sea level or very close to see level 

Edited July 10, 20195 yr by Evan

On 7/9/2019 at 11:02 PM, Evan said:

A 24v will compensate for altitude well not altitude but the lack of air. It will adjust the fuel air ratio timming everything really.

 

No compensation. 

 

As you go up you foot goes down more fuel is added. There is no air / fuel ratio nothing to measure or monitor it. Timing is controlled by your foot once you pass 20% engine load the timing just retards deeply that all. The key factor is IAT below 80°F then timing advances. Above 80°F then it retards. I live in a area where I can go to 9,000 plus feet above sea level (Heavens Gate - Riggins, ID) and drop to as low as 800 above sea level (Lewiston, ID). 

 

Fueling is based on boost. As you climb in elevation the air gets thinner and the turbo has tough time making same amount of boost. Since the fueling is based off of boost this just limits the power you can create even in stock form. You can't have max fuel will little to no boost. Boost pressure is the key to releasing more fuel. 

 

Once you have a Quadzilla and able to monitor live data in flight then you start understand much more. So climbing I'm typically about 14° BTDC and well over 35% engine load which means more fuel. My cutoff is 20% engine load then there is a -3° of timing based on engine load as load increases the timing advances. Then on the flat it settles to about 22° BTDC and a mere 15 to 17% engine load at 65 MPH. I  climb 3 grades twice a day. Travel 1,000 miles a week.

 

On 7/9/2019 at 11:02 PM, Evan said:

Itl always push the same timming and fuel unless you physically change it.

 

Not true. Even stock has its limits and will not keep same timing all the time. Again even running Quadzilla in Level 0 you can monitor STOCK ECM fuel and timing and its VERY dynamic and changes constantly. Stock ECM can dip very low in timing and can rise up to extremely timing at high RPM's.

Edited July 12, 20195 yr by Mopar1973Man

I ordered a set of 5x.012 injectors and asked that they be set at 305bar. Hopefully this will get me a bit cleaner burn and add a little mpg too.

Almost forgot about this rig is saw out in Colorado. I couldn’t get very good pics but you get the jist of it. It was a second gen with a wild paint scheme, pretty tough looking rig.

 

Edited July 19, 20195 yr by 98whitelightnin

On ‎7‎/‎12‎/‎2019 at 6:40 AM, Mopar1973Man said:

Itl always push the same timming and fuel unless you physically change it.

 

@Mopar1973Man, I think @Evanis referring to the 12 valve engine here.

 

- John

Doesnt matter what I'm talking about.

I set the timing at 16.5* last week and have been checking get temps on a certain part of my commute and they are constantly 50-60 cooler. 

 

Got the PDD 5x.012 sac injectors @ 305 bar in yesterday and they really woke the truck up! It runs strong and really clean, unless you really get on it. I’m still running stock gsk and I can definitely feel the new throttle response. They lowered my idle about 50 rpm so I need to bump that up. 

Edited July 25, 20195 yr by 98whitelightnin