98 explorer cranks won't start
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Freshman User
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From: Florida
98 explorer cranks won't start
Ok here we go I have a 98 Explorer with the 4.0 SOHC. The wife went to start this morning and it won't. It cranks and the fuel pump will come on for about 2 seconds with the key on. I have not put a pressure gage on the rail but did push in the pin on the valve and it has pressure
. Pull a plug an cranked the engine with the plug grounded and have spark.
I pulled the codes and had 9:
P0430 mod Catalyst below threshold bank 2
P0301 cyl. 1 misfire
P0302 cyl. 2 misfire
P0303 cyl. 3 misfire
P0304 cyl. 4 misfire
P0305 cyl. 5 misfire
P0306 cyl. 6 misfire
P0171 system to lean bank 1
P0174 system to lean bank 2
I guess with all the cyclinders miss fires I am thinking that the crank shaft sensor is bad. My other thought is maybe the timing chain I hope not. The guy at the Parts store thought I should test the fuel pressure first. Anyone know of a way to test the crank shaft sensor or have any other thoughts.
Thanks in advance for any help.
. Pull a plug an cranked the engine with the plug grounded and have spark.
I pulled the codes and had 9:
P0430 mod Catalyst below threshold bank 2
P0301 cyl. 1 misfire
P0302 cyl. 2 misfire
P0303 cyl. 3 misfire
P0304 cyl. 4 misfire
P0305 cyl. 5 misfire
P0306 cyl. 6 misfire
P0171 system to lean bank 1
P0174 system to lean bank 2
I guess with all the cyclinders miss fires I am thinking that the crank shaft sensor is bad. My other thought is maybe the timing chain I hope not. The guy at the Parts store thought I should test the fuel pressure first. Anyone know of a way to test the crank shaft sensor or have any other thoughts.
Thanks in advance for any help.
Last edited by mr.l; Dec 6, 2006 at 07:00 PM.
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Wow you must have been driving it for some time with the check engine light on.
Personally I'd be looking for a vacuum leak.. I've had some of these with leaking intakes that just would not start when it's cold out... maybe try it again when it's a tad warmer.
Usually it'll set a different code if you lose a crank sensor or something, it's VERY odd to have misfire codes on all six cylinders... unless they've been intermittantly missing from time to time in the past (which would be hard for you to tell being you've been driving it with the light on)...
Anyways... do this.. unplug the Mass Air Flow sensor (right above the air filter) and see if it starts.. if not... I'd suggest a compression test and getting the static timing verified... or you could just throw intake gaskets on that sucker and see what happens...
This should address your lean codes, and possibly the misfire codes... the
catalyst efficiency code has nothing to do with it not starting.. worry about that later.
If you do manage to get it running, I would SERIOUSLY suggest a compression test... I'm baffled by the misses on all 6 cylinders...
Personally I'd be looking for a vacuum leak.. I've had some of these with leaking intakes that just would not start when it's cold out... maybe try it again when it's a tad warmer.
Usually it'll set a different code if you lose a crank sensor or something, it's VERY odd to have misfire codes on all six cylinders... unless they've been intermittantly missing from time to time in the past (which would be hard for you to tell being you've been driving it with the light on)...
Anyways... do this.. unplug the Mass Air Flow sensor (right above the air filter) and see if it starts.. if not... I'd suggest a compression test and getting the static timing verified... or you could just throw intake gaskets on that sucker and see what happens...
This should address your lean codes, and possibly the misfire codes... the
catalyst efficiency code has nothing to do with it not starting.. worry about that later.
If you do manage to get it running, I would SERIOUSLY suggest a compression test... I'm baffled by the misses on all 6 cylinders...
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From: Florida
Thanks for the help MazdaRangerGuy.
Yes, the check engine light has been on for a while. About 18 months back it was running rough and would stall when engine was warmed up. When we had the codes pulled the mechanic said it was the IAC valve. I change the valve then it would not stall when warmed up but still ran rough at start-up.
About 8 months back I saw on this forum how to check the intake using carb cleaner. I checked the intake with carb cleaner and the gaskets needed to be changed. I did change the gaskets but it still ran rough at start-up it ran smooth once the engine warmed up. I checked the intake again with carb cleaner did not notice any idol changes.
We live in Florida I know it is very cold in other parts of the country this time of the year. Our temperature is in the low 70’s is that cool enough to be a factor?
Yes, the check engine light has been on for a while. About 18 months back it was running rough and would stall when engine was warmed up. When we had the codes pulled the mechanic said it was the IAC valve. I change the valve then it would not stall when warmed up but still ran rough at start-up.
About 8 months back I saw on this forum how to check the intake using carb cleaner. I checked the intake with carb cleaner and the gaskets needed to be changed. I did change the gaskets but it still ran rough at start-up it ran smooth once the engine warmed up. I checked the intake again with carb cleaner did not notice any idol changes.
We live in Florida I know it is very cold in other parts of the country this time of the year. Our temperature is in the low 70’s is that cool enough to be a factor?
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OK.. now I have to wonder if you have water (antifreeze) getting into the combustion chambers... some water leaks in during engine cooldown, and when you start it up, it'll run rough until the water evaporates out of the cylinders, not real common but if you have a lot of miles a very good possibility.
Try this.. drive it until it's good and hot.. then park it and let it cool down completely... without starting it, remove the spark plugs and look for evidence of moisture on the plugs... also you might try a mirror and flashlight to look down into the cylinders (through the spark plug holes) and look for moisture.
Have you been having to add antifreeze at all?
Try this.. drive it until it's good and hot.. then park it and let it cool down completely... without starting it, remove the spark plugs and look for evidence of moisture on the plugs... also you might try a mirror and flashlight to look down into the cylinders (through the spark plug holes) and look for moisture.
Have you been having to add antifreeze at all?
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From: Florida
Right now the truck still will not start.
It will crank and has spark at the one plug I pulled. So I am guessing that the crankshaft sensor is working to make the coil pack pulse. But the spark did not look that bright. The Haynes Manual shows a calibrated igntion tester are they any good? The last time I changed the plugs my wife picked up those Bosch ones with the small electrode.
I am thinking about buying a new set of plugs.
It will crank and has spark at the one plug I pulled. So I am guessing that the crankshaft sensor is working to make the coil pack pulse. But the spark did not look that bright. The Haynes Manual shows a calibrated igntion tester are they any good? The last time I changed the plugs my wife picked up those Bosch ones with the small electrode.
I am thinking about buying a new set of plugs.
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From: Florida
Did a cylinder compression test only getting 40-45 psi on all cylinders but it will hold it. I looked down the oil fill cap can see the chain moving when cranking the motor. Is it possible that it has jumped time? Maybe the valves are open part way through the compression stoke?
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From: Florida
I have put in new plugs.
Have spark at the plugs.
Checked fuel pressure at rail while cranking motor has 50 psi.
Have positive power at injectors with key on.
Get a pulse on the ground at injector when cranking motor.
Still will not start.
Have done a cold compression test only getting 45-55 psi at each cylinder.
Leave gage on cylinder for over 2 hours only dropped 2 psi.
I am thinking the timing chain has jumped and a valve is open during compression stoke. I am thinking this would explain why low compression but the valves and rings are good so it can keep pressure for over two hours.
Anyone have any thoughts?
Have spark at the plugs.
Checked fuel pressure at rail while cranking motor has 50 psi.
Have positive power at injectors with key on.
Get a pulse on the ground at injector when cranking motor.
Still will not start.
Have done a cold compression test only getting 45-55 psi at each cylinder.
Leave gage on cylinder for over 2 hours only dropped 2 psi.
I am thinking the timing chain has jumped and a valve is open during compression stoke. I am thinking this would explain why low compression but the valves and rings are good so it can keep pressure for over two hours.
Anyone have any thoughts?
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Thread Starter
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Freshman User
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From: Florida
Thanks for seconding my diagnosis. It was the only thing that I could think of that would explain low compression but would let the motor maintain pressure for a period of time. I am going to start tearing it down tomorrow. I will know for sure when I see the timing chain and gears.
Thanks again.
Thanks again.
Cargo Master
Joined: Aug 2003
Posts: 3,263
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From: BC Canada
mr.I
Since all 6 cyl are low I would be looking for something common beween the 2 banks. Having given it some more thought I am not sure both chains would have skipped a tooth.
Maybe the bottom keyway stripped, just a thought..... make it TDC on No1 before you strip it.
Keep us informed, I will be hovering over your shoulder!
Since all 6 cyl are low I would be looking for something common beween the 2 banks. Having given it some more thought I am not sure both chains would have skipped a tooth.
Maybe the bottom keyway stripped, just a thought..... make it TDC on No1 before you strip it.
Keep us informed, I will be hovering over your shoulder!
Cargo Master
Joined: Aug 2003
Posts: 3,263
Likes: 92
From: BC Canada
well I was not satisfied waiting, the "Jackshaft chain" is common to both banks
Do you have a good repair manual and an accurate torque wrench?
Ford manual calls for removing the engine to do this job.
If I can help, PM me.. Good luck
Do you have a good repair manual and an accurate torque wrench?
Ford manual calls for removing the engine to do this job.
If I can help, PM me.. Good luck
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Freshman User
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From: Florida
Yup. Got the timing chain cover off today the jackshaft chain tensioner is missing and the chain and cassette for left camshaft is damaged and lose. Looks like the will be coming out.
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I had the same problem with a 98 Explorer with 93,000 miles, never failed to start. Parked in the garage one day, the next day it would not start. I checked for spark and fuel as you have done. The problem was the crank sensor. Twenty dollar part cost me $150 for towing and replacement.
Cargo Master
Joined: Dec 2004
Posts: 2,232
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From: NE Texas
Yep, in the old days of the morse timing chains, it was not uncommon to see the chain jump a tooth out of nowhere. The low compression on all cylinders is everything short of a total guarantee that this is the problem.
Good luck with it,
Good luck with it,