Slow start now no start (3 Viewers)

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Oct 4, 2017
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So I've already cruised the forums here and other places and cannot find an answer so here goes. I was having a slow start issue for several weeks. I went ahead and replaced the battery and starter. After i got done replacing the starter the truck did start up like it did before, no improvement, maybe stronger cranking being a new starter but pretty much same long crank before eventually starting. It ran fine, i drove it around the block, turned it off and started it again, seemed normal as in same as it was before the starter being put in, slow starts. I woke up the next day to go to work, it wouldnt start. It cranks and cranks and cranks but wouldnt start.

So heres what ive checked so far. Ive check all fuses in engine and in car, none blown. Ive replaced the efi relay and efi fuse. I took off the fuel hose coming off the fuel filter and when its cranked fuel gushes out. I took the coil and plug out and grounded it and cranked the engine, i had no spark, and i didnt smell fuel coming out of the spark plug hole so i assume no fuel coming out of the injector.

Now I do have some trouble codes at this point. One is p1300, this code has been on and off for a couple months, ive already replaced this coil but it only comes on when the engine is warmed up and rev'ed above 4000-4500 rpm's, it shudders, misfires and the light comes on. It rev's all the way up when cold no problem. When the truck sits over night the code went off by itself and it otherwise drove fine as long as i didnt push it. Its back and staying on now.

Second code is p0340. This is a new code that only came on after the completely no start issue. i did hook up my reader after the starter replacement and there were no codes at that time. Now it wont start, now i have this code. I pull off as much as i could without further disassembly the driver side timing cover and the belt looked in good shape, no fraying or cracks or anything. i also tested what i believe to be the wires leading to the cam position sensor, i forget what the resistance was but it was not an open circuit fwiw.

Tired of throwing parts at it wondering if any of this sounds familiar to anyone...Thanks
 
I'm sorry to hear you having starting problems, I know that's aggravating. There's a good chance I won't know the fix for your ride, but you've piqued my interest.

When you say it has "slow start issues" do you mean that it's turning over slow, or it turns fine but takes longer than it should to fire?

Hopefully someone more knowledgeable than me can pinpoint your issue soon.
 
Slow start meaning it cranked like usual but took longer to fire. I also ruled out immobilizer because 1, i have no codes for that, and 2, the red key light goes off when the key in inserted. I also tried starting with the gas cap on/off. Still no start.
 
Is your 100 from Ohio originally? I would check the ground straps from the starter, fuse block, alt., and rear of the engine. I had some of the same symptoms and it turned out the grounds were corroded and not making good enough contact. I also replaced the fuel filter which seemed to help out a bit too.
 
Post your vehicle deets: year, mileage, PM status; that'll help knowledgeable folks narrow it down. Fuel filter crossed my mind, too. Great Ohio minds think alike.
 
If it is cranking hard, but not firing, I think you are headed down the right path of fuel or air issue. Air filter clean or new? fuel filter is cheap and easy to throw at it if it has not been replaced recently. Any chance you got some crap gas? just some thoughts....
 
its a 2000, 345k. I bought from original owner, and assume it spent its whole life in ohio. If your talking about the ground that came off the starter, i sanded the connection and the engine block where it sat when i changed the starter, im fairly confidant that connection is good. what other grounds should i check? New air filter about 5k miles ago. The most telling test ive done so far is pulling the plug and coil and grounding the plug and cranking the engine, i got no spark from the plug and no fuel smell coming from the spark plug tube out of the cylinder, there is fuel pumping out of the fuel filter when cranked though.
 
You might also smell the engine compartment for gas....from the fuel tank to the engine. If you have a small fuel leak, it could be losing prime.
 
No gas smell. Seems to me that if i have gas coming out of the fuel filter, and power going to the starter, but no gas coming out of the injector and no spark, theres an electrical disconnect somewhere, i just dont even know where to start looking. p1300 and p0340 are both bank 1 codes so maybe something coming off that harness? does anyone have a diagram to point me where to start looking? Seeing that the fuel pump is pumping and starting is turning can i eliminate anything under the dash and look more locally in the area near the components throwing the codes?
 
Spark plugs newer or in good shape?
 
replaced all spark plugs 2 months ago. I replaced the alternator 3 months ago, double checked the connections and ground there as well.
 
You need to check your fuel pressure at the engine, just because it looks like you have adequate fuel coming out of the fuel filter it does not mean there is enough pressure to run the engine.
It sounds to me like your fuel pressure is bleeding down overnight, so it takes longer to start because the fuel pump has to rebuild fuel pressure in the system.
Soooo, you nee to check fuel pressure at the engine, I do not know how to do it on this engine, but usually there is a port that a fuel pressure tester plugs into.
Low fuel pressure after sitting is a sign of a failing fuel pump.
 
How’s your throttle body?

Uncle’s 2000 did the same thing. Slow start gradually got worse until no start. He cleaned all the crap out of the throttle body and now it’s fine.

The 2UZ doesn’t use a separate air control valve for the idle, so if crap builds up around the butterfly the idle gets choked off.

I cleaned the throttle body on our 1999 and it now starts quicker and idles waaaay higher. Once the computer figures out it can breathe properly it should settle down.
 
Here are the resistance values for the cam sensor


upload_2018-8-19_18-2-10.png
 
I cleaned the throttle body and intake when i did the starter. I will test for the fuel pressure, but i dont see how that would lead to the no spark issue. Would the camshaft position sensor malfunction cause no spark?
 
I cleaned the throttle body and intake when i did the starter. I will test for the fuel pressure, but i dont see how that would lead to the no spark issue. Would the camshaft position sensor malfunction cause no spark?

It can if the ECM is relying on the cam sensor (among others) to control the ignition
 
Long crank is often associated with leaky fuel injectors. But this has nothing to do with NO spark. I suspect a crank or cam sensor issue. Have you noticed any signs of rodents, they love our wires.

The engine wire harness runs around the top of the heads and down the LH front to cam & crank sensors. All wire come togehter at rear of engine, which you saw replacing the starter. Then through firewall on PS to ECM/ECU behind glove box.

Here are the resistance values for the cam sensor


View attachment 1770785
Is this from a 100 series FSM. I ask because I can't think of "V bank cover" on the 4.7L.
 
i didnt notice any signs of rodents, there was no debris in the v of the engine when i took the intake off but this has been my daily since i got it last october and was a daily for the previous owner before that so im not sure it would attract that sort of thing. Any particular place to check the wiring where the injectors and plugs are both controlled off the same harness from that point forward, but not the starter motor?
 
95% of no-start issues are electrical. If you have verified a lack of spark at the plugs, forget about the fuel system until you've got firing plugs. That would be my approach. On the other hand, I am NOT a great mechanic.
 
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