Hard starting, everything else fine?

[Doug]

I have one bug trying to fix on the new 5.0 install in my 93 NAS 110. It's actually a problem I've had for a few months, but seems worse with the new engine -- and that is it takes numerous cranks and tweaking the gas to get her to fire up. Truck has a very recent new fuel pump and filter.

Once running, idle is fine, no hesitation, revs are great, no fault codes. Anyone have a simple checklist for this issue?

[rover4x4]

just a thought but......... maybe the starter was getting worn with the 3.9 and now with the larger motor the effects are more noticable? just a thought isnt thte 5.0 higher compression etc?

[TwisteD90]

Doug, did you replace the whole fuel pump assembly or just the pump it self. I had the same problem with mine and it turned out the sender hose from the pump was loose.

[Doug]

Ahhh, good idea! I'll check that, Yousef. Phil, the engine came with new starter -- it cranks fine, but thanks for the idea.

Can any of the various senders cause a hard start as above?

[rover4x4]

how's the battery. j-jk

[Doug]

Just read on LRX that bad fuel and coolant temp sensors can cause this prob. Have to check them. Phil, batt is good!

[neo812]

Doug, seems as though you have found my suggestion. Both of these items can cause the problems you are mentioning. Buy genuine. I matched the sensors at NAPA when I was tracking down the same problem. They did not fix it and now I have a toolbox full of useless sensors. The genuine seemed to do the trick.
Motorcars LTD. in Houston has about the best prices on those sensors.

[Doug]

Well, the sensors are all the new ones with the new engine. Can't be them. Fuel pressure seems fine. But we noticed that when the starter is cranking, there doesn't seem to be much spark. Alternator is new, battery is a year old yellow top that seems fully charged.

Any ideas what could be sucking off ignition spark only when the starter is cranking?

[Robbie Donaldson]

is this a distributor or gems truck? if a distributor, i would look at the rotor and cap. possibly even the coil.

had a rotor go bad on my 3.9 and made very weak spark at the plug wires, to the point wouldn't even start.

[Doug]

New coil, and its the spark coming from the coil lead to the disty that dips on cranking. Let go the starter, and the spark improves. BTW, the problem was present before new engine and new starter motor.

[Bowtracer]

Doug how many wires do you have going to your coil? You may have dropped one on the eng swap? Only a stab in the dark! Ignition module?
How bout checking the amplifier switching. Iwill try to scan & post if needed.
Peter

[Doug]

Wow, maybe! How many wires are supposed to be going to the coil pos and neg? Amplifier is only 5 months old....

[Bowtracer]

Doug, 2 white pos 2 white neg & the little black to what ever that is on the fender. Do you wana pic? I pulled my coil& turn it upside down so you can see.

[Doug]

Can you post the pic? Thx

[Bowtracer]

I will tonight! I was racing all day & I am spent.
Peter

[Bowtracer]

they are not the best but hope they help

[Doug]

Thanks Peter -- I'll match these up tomorrow and let you guys know if all the wires are in place!