I have a 99 limited. New battery (optima), new starter. On mornings below about 10, it will not start. It cranks just fine, but will not catch. Pumping the gas does nothing. I sprayed starting fluid in the intake this morning, nothing. I spoke to the dealer today. He told me that I may have too much alcohol in my gas, and I should use a lower octane gas next time. I put Heet in tonight. I will see if it starts tomorrow. Thoughts on what be my problem is?
Won't start on cold mornings
- Thread starter Bonedale
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JayRolla
New member
So it doesnt sound like its a power issue with the new battery and starter. If you have a multimeter you can test the voltage when cranking to see if its dropping to low but thats most likely fine.
To me it sounds like an ignition issue. Maybe older spark plugs, wires or incorrectly gapped plugs. Maybe even a weak coil pack.
Its not the ethanol in the fuel. Me and buddys run 85% ethanol fuel in our turbo cars and they still start. Its hard but it starts. Regular gas has 10-15% ethanol which is not enough to make it hard to start.
To me it sounds like an ignition issue. Maybe older spark plugs, wires or incorrectly gapped plugs. Maybe even a weak coil pack.
Its not the ethanol in the fuel. Me and buddys run 85% ethanol fuel in our turbo cars and they still start. Its hard but it starts. Regular gas has 10-15% ethanol which is not enough to make it hard to start.
Illestreker
New member
A few days ago when we had the coldest temps recently, my truck at outside for about 3 days without running (not that it didn't start, but I just never drove it) and when I went to start it after those 3 days its struggled to start for about 3 seconds then finally turned over.
I have had my truck for several months now but its the first time ive had it in super cold weather and its never done this to me. It normally starts right up with absolutely no hesitation.
To me it seems odd that yours wont turn over even if you keep trying especially given the maintenance it has. Maybe bad gas in combo with low temps?
I have had my truck for several months now but its the first time ive had it in super cold weather and its never done this to me. It normally starts right up with absolutely no hesitation.
To me it seems odd that yours wont turn over even if you keep trying especially given the maintenance it has. Maybe bad gas in combo with low temps?
19963.4lsr5
New member
Low fuel pressure or dirty fuel filter?
It's not hard checking fuel pressure. Just need a pressure tester. Then ignition on and before starting check the pressure at the schreader valve.
If you have good pressure then its on to checking for spark. And that as easy as pulling a plug wire out of a drivers side cylinder and putting a spark plug in it and have someone watch for spark while you try to start.
It's not hard checking fuel pressure. Just need a pressure tester. Then ignition on and before starting check the pressure at the schreader valve.
If you have good pressure then its on to checking for spark. And that as easy as pulling a plug wire out of a drivers side cylinder and putting a spark plug in it and have someone watch for spark while you try to start.
Thanks for all of the replies. You guys already sound more knowledgable then the guys at the dealer.
New fuel filter a few months ago, but I guess it could be fuel pressure. I'll look into a pressure sensor.
New plugs a few months ago, but I did them myself, so maybe I didn't gap them properly. Coil pack- what is it like to replace that? That sounds promising.
New fuel filter a few months ago, but I guess it could be fuel pressure. I'll look into a pressure sensor.
New plugs a few months ago, but I did them myself, so maybe I didn't gap them properly. Coil pack- what is it like to replace that? That sounds promising.
Brignola85
New member
The coil packs are simply the "Plug and wire" that fit over top of your spark plugs. They pull right off and snap right back on. I'd recommend going DENSO if you hadn't done them when you replaced the spark plugs..
EatonKyleH
New member
Where in Colorado are you?
Since you gave it another fuel source with starting fluid and it still did not change it is highly unlikely to be a fuel problem unless it was already flooded(with fuel) which in that case would still rule out fuel restriction and such.
Do you know how to test for spark and/or RPM signal? It is not extremely uncommon for the Crank signal to the computer to drop out in extreme cold from a weak sensor. This results in no spark and no injector pulse hence a crank no start scenario.
Also when this occurs turn the key on and see if the Check engine light illuminates when the key is turned on like it should for its bulb check. If the light does not come on when cycled during your starting problems it's a common tell tale of a sticking EFI relay typically.
I would stop short of claiming that's what it is in your case without proper diagnostics but if you are anywhere near Fort Collins feel free to PM me.
Good Luck!
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I'm in Carbondale, outside of Aspen. I'll try replacing the EFI relay, maybe that will do it. Here's a crazy idea: since I can't make it to the parts store between now and tomorrow, what if try to start the truck- if it doesn't start, I pull the relay, let the relay warm up inside for a while, then plug it back in and try to start the truck again. Is that a bad idea? Or maybe I'm missing the concept altogether-
19963.4lsr5
New member
Take your ICM inside and warm it up then see if it will start.
If it won't start with starting fluid.....you opened the throttle plate and did a 1 or 2 second spray directly into the intake, correct?
If you didn't do it the above way do it that way and see if you have the same results.
If it won't start with starting fluid.....you opened the throttle plate and did a 1 or 2 second spray directly into the intake, correct?
If you didn't do it the above way do it that way and see if you have the same results.
TheDurk
Elite Member
Pretty sure there are identical relays in the truck you can swap for a quick test. Compare part numbers to find a twin. If it were warmer I'd go look for you but it's serious cold here, too.
We had a problem similar to this a few years back on my dads 91 with 3vze. I know its not the same motor. It would start when only 0f but when it got to -30 it would turn over fine but not fire. Turned out to be the o2 sensor. Same on my grandpa's 92. My 99 has no problem starting at -30 right now. Fires immediately. Check the o2 sensor if nothing else is found. Can you plug it in to check if it starts with warm coolant?
19963.4lsr5
New member
How did you spray starting fluid into the engine? Through the throttlebody or into the airbox?
Grenvilleter
New member
Dumb question and too lazy to look it up but, can you disable the starter so you can cycle the ignition over to the "engage starter" mode and listen for the fuel pump to turn on ?
That would tell you at least the fuel pump is operating without ripping it apart in this cold weather.
It could be something stupid like thermal contraction on the fuel pump wire harness on an improperly plugged connector or a fuel pump that refuses to run when it's too cold.
I know...grasping at straws here but if you can confirm the fuel pump is running when it's told to, it rules out some potential problems.
Oh...and BTW, did you put some gas line anti-freeze in it?
That would tell you at least the fuel pump is operating without ripping it apart in this cold weather.
It could be something stupid like thermal contraction on the fuel pump wire harness on an improperly plugged connector or a fuel pump that refuses to run when it's too cold.
I know...grasping at straws here but if you can confirm the fuel pump is running when it's told to, it rules out some potential problems.
Oh...and BTW, did you put some gas line anti-freeze in it?
When I sprayed starting fluid in, I sprayed it into the air box (after removing the filter). I wasn't about to start ripping things apart when it was -4. I had the same thought about the fuel pump. Maybe it just doesn't like cold weather. Oh, I put Heet it in a few days ago. Doesn't seemed to have made much difference.
I put the new EFI relay in. We'll see if it starts tomorrow. If it doesn't I will probably bring it to a mechanic (maybe an O2 sensor first). I need to stop bumming rides to work.
I put the new EFI relay in. We'll see if it starts tomorrow. If it doesn't I will probably bring it to a mechanic (maybe an O2 sensor first). I need to stop bumming rides to work.
Grenvilleter
New member
Maybe before you go to bed you can put a incandescent light bulb or 2 under your hood to try to warm up the TPS & crank sensor area's.
It will also help warm up the block especially if you run 100 watt bulbs.
May not cure your problem but might get you to work tomorrow.
Also a hair dryer on these electronic sensors may warm them enough to let them start functioning again.
Of course that's assuming your getting fuel up.
Again...costs nothing to try out.
It will also help warm up the block especially if you run 100 watt bulbs.
May not cure your problem but might get you to work tomorrow.
Also a hair dryer on these electronic sensors may warm them enough to let them start functioning again.
Of course that's assuming your getting fuel up.
Again...costs nothing to try out.
19963.4lsr5
New member
You need to spray it directly into the intake. That ether doesn't last long.
At the very least you should have held the throttle wide open when spraying into the air box.
I know people will argue but the proper way is to open throttle and shoot a 1 to 2 sec blast directly into the intake.
Unless you use the starting fluid correctly you can't eliminate fuel delivery as a problem. (Since you can't measure fuel pressure at the rail)
If you spray into the intake plenum and it starts its fuel delivery. If it still doesn't its ignition. Which could be the crank sensor or the ignition module.
Have you pulled a plug wire and checked for spark when it doesn't start. Its simple. Pull the front drivers side plug wire. Stick a screwdriver in it and hold 1/4 inch from metal and have someone try and start it.
If no spark you know where to go next. If spark its back to fuel delivery. (Pump, filter, cam sensor)
GA-4RUNNER
New member
A block heater would be the first thing i would invest in.
I do not recommend ether or starting fluid to be used on a daily basis
I do not recommend ether or starting fluid to be used on a daily basis
