Engine/Transmission (1994 - 1998) using a little pedal to start the truck question

[UhhhDawson]

hello hello. 98 12v qcsb 4x4 2500. my first CTD was a 93. one thing i loved about it was the instantanious engine start up when i turned the ignition. now i love my 98, but am curious about one thing. if i dont press the accelerator when i start the truck the starter turns over a few times and the engine will slowly come to life. but if i even barely rest my foot on the accelerator the start up is instantanious just like my 93. is there a part i need to replace to make this happen without having to use the pedal? this would really help me during the winter, because normally i have to hold my foot on the accelerator and hold the truck at rpms for a few seconds or it will die, where in my 93 it would fire right up no matter what the temp. .



hope this makes sense and thanks in advance for any help/advice!

 

[WDixon27]

probably need to bump the idle up a little, i set mine around 730-750 and need to give it a little pedal to start but it doesn't die, it should be a little higher but i like mine low

 

[BTighe]

if i remember right the manual says to give it some when starting. i always rested my foot about half throttle and popped off when i heard it fire. worked fine and if i was too slow a nice puff sounds normal to me.

 

[Missouri Mule]

I agree try setting your idle up;

Auto trans 750-800 rpm in drive with ac on.

Manual trans 780 rpm in neutral with ac on.



I have read some where this is also a symptom that your starter is going or at least not turning fast enough but haven't confirmed it.

You mite want to check batteries and clean terminals on battery and starter.

 

[DonTX]

My first gen started instantly without foot feed, my 97 will start instantly if I give it a little pedal, but cranks longer if you don't give it any.

There was a thread on this earlier, it seemed most 7100 pumps need a little pedal to start instantly, but there were some reporting not having to give pedal, but not many. I am getting trained to just give it a little pedal.

 

[Kiohio]

Mine needed pedal until I changed the fuel filter.
Not that that is your issue but that is how mine responded.
Truck has been sitting (because of the bad rearend) and I started it up a few days ago.
No pedal... rolled over about a 1/2 turn and fired up.
The 2nd gens still seem to start sluggish compared to the 1st gens.
BUT neither are as sluggish as the 24valves, 3rd gens especially.

KO

 

[Tom C]

I think it's "luck of the draw" whether you get a truck that needs pedal or not to start instantly.



I had a '95 once that when I bought it would need a push on the pedal to start. But then after a couple of cross country runs it would start instant without pedal... . figures. .



My current truck takes a little push of the pedal. I've crossed country a few time with it and do difference. ow-well, I just got used to it.

 

[champspa]

mine needs pedal , always has. just rest your foot on it

 

[DonFitzwater]

Joe G expained it to me like this: Basically it's a bit of slop in the pump and if you gently push the pedal all of the slop is removed and wammo, it starts immediately. It does help if you have a your idle set correctly... ..... somewhat.

 

[JFaughn]

No gauges in your sig. , but then most 12vers do not put fuel pressure in , mostly the later troublesome fuel systems .
I would check fuel pressure , overflow valve , lift pump , and put 10-15% bio-diesel for 2 tank fulls , carry a spare fuel filter , bio is the only thing that will clean the fuel system to the point of plugging the filter .
I agree with above , RPMs 800-850 .

 

[fest3er]

My first gen started instantly without foot feed, my 97 will start instantly if I give it a little pedal, but cranks longer if you don't give it any.

There was a thread on this earlier, it seemed most 7100 pumps need a little pedal to start instantly, but there were some reporting not having to give pedal, but not many. I am getting trained to just give it a little pedal.

My '98 12V fires up with 1/8 to 1/4 second of cranking, no pedal. Down to maybe 20F with one or two heater cycles, it starts PDQ as well. I've only had to give it pedal when it's 0F or colder.



So why do some 12Vs start instantly and others take longer?



N

 

[CumminsPower98]

Mine starts fast in the winter (even when hot) but as soon as summer comes around it cranks a bit and needs the slight peddle input for an instant start. My idle is correct and when I did increase it once it made little to no difference. I have always wondered about this. I do have a fuel pressure gauge and have replaced the lift pump and overflow valve in the past. It's has to be something in the P7100 but I sure don't know what causes it. I haven't seen anyone talk about temperature yet, which changes how mine acts. The truck now has 388k miles but has always been this way from 67k when I got it.

 

[MMcCallie]

My idle has to be set to at least 900 RPMs to not need pedal to start. When i'm off road i like my idle around 500 RPMs for crawling but then i stall often, even with an automatic. I've swapped the pump and injectors and i almost have to say that the stock 160 setup started faster.

I've become used to giving it pedal to start. I'd rather give pedal for a quick start than make the starter keep spinning the flexplate until there is finally enough compression to ignite the fuel. Definitely check the regular maintenance as previously mentioned, fuel filter, overflow valve, lift pump. I will someday install a fuel pressure gauge.

 

[LDPetersen]

My 92' started instantly with no pedal. My 95' needs a little pedal to start instantly. I do agree with the idle. Mine is a little too slow now with the A/C running. I did find out after i put the Larry B's kit in for the bad fuel lines, mine starts great. It does say on the sun visor to give it a little pedal. Larry.

 

[The patriot]

MIne has always needed some petal since I lowered it.

Dealer had it idling @ almost 1000 RPM:-{} when I picked it up in 1997.

I lowered it the next day, and since then I needed a little petal.

Eric

 

[wcjp]

When I first bought the 96' 5spd it started slow. After replacing the fuel supply/return, lift pump-fuel preheater soft line and starter contacts it started instantly.

 

[CHolmsten]

I remember hearing somewhere that its because the VE starts out at max fuel when starting it, but the P7100 doesent. Hence the required pedal. . .

 

[DonTX]

I suspect you are correct. I know my 8V71 Detroit always started with about a fourth of a revolution. The reason for that was that when shut off the nature of those gives it a full fuel setting when cranking.

 

[JGK]

The pump is designed to move the governor lever (referred to as the fulcrum lever by the Bosch folks) to full forward rack travel by just giving it a bit of throttle when you bump the key. This assumes you have not adjusted the lever to be above the tip of the stop plate - a common adjustment described on the piersdiesel.com (pdr.com) site. As soon as it lights and the revs get past about 300 the governor pulls the lever back, raises it, and places it on the stop plate - or actually on the AFC lever. If I understood the Bosch gurus correctly, all P7100s are designed to do this.



EDIT, 1/23/08: I want to correct the above statement. During my conversation with the Bosch tech that was explaining this to me, in his enthusiasm, he had switched gears on me and was referring to the P7100 pump in a different application but I didn't catch it. In fact, the lever does not go under the plate and go to max travel with a little throttle at start. It does come forward, but only to contact the plate.



Now with the 215 pump, a feature was added. Called the retard notch, it is machined into the top of each plunger. It is actually an "advance" notch that adds fuel. In the start phase when the lever goes full forward with a blip of the pedal as you bump the key, the rack twists the plungers until this notch lines up with the spill port and a tad more fuel is added at start. Plus, the notch ads a few degrees of advance timing during this phase. This was done to the 215 pumps in response to tighter emission requirements that dictated a quicker/cleaner start up. Somehow, this notch makes that work.



EDIT, 1/23/08: True, there is the retard notch, but I'm not clear now just exactly how that works for us on our 215 pumps on start up. I'll need to go back and clarify that when I get a chance.



Now a lot of long-time 12valvers will argue with me about having the lever under the plate. I hear you. Mine has been that way for about 4 or 5 years. And the truck started and ran fine. But I just had my pump rebuilt due to a broken rack stop pin and trashed governor weights and I had the opportunity to talk quite a while with 2 Bosch-certified techs with combined experience of over 40 years. What I related above is what they told me. Who am I to question?! In any case they adjusted the lever on mine below the plate and it starts on the first pop and runs like a banshee, so for now I won't change it.



EDIT, 1/23/08: I have not modified where the governor, or fulcrum, lever contacts the plate on start-up since they rebuilt my pump, but the truck still starts on the first pop or two. Now that winter is here, if I fail to plug in the truck at night and it gets down to the low 20's or lower, it takes a few more pops to start, but it has always been that way. Again, when I get a chance, I'll go in and get clarification and update this post.



For what its worth,

-Jay

 

[Kalaehina]

No pedal, instant fire up for the first 2 years, now it needs just a slight push to fire up instantly like before.