Need help with cranking problem

[Stick4503]

I have a 1996 explorer with the 4.0 pushrod engine. It seems to crank fine the first time, morning afternoon hot or cold does not matter, but after driving to a store or somewhere when I try to get it started the engine turns over fine but only fires off like 2 or 3 cylinders are firing this last just a few seconds and if you don't gas it just right the engine dies and takes multiple attempts to get it cranked. During these attempts the engine does not seem to fire at all.

I have replaced the fuel filter and this did not help.

I attempted to rent a fuel pressure gauge but it seems that people destroy them so they don't work. I have strong fuel pressure at all times, just not sure of the psi.

I have opened the filler cap while attempting to start it and thought that I found the problem, however after several attempts at this it seems that the engine just happened to start, unrelated to the cap.

I have however opened the cap while the engine is running and on occasion have the engine begin sputtering and almost go dead but then return to normal.

During any and all of this I have never got a fault code.

I have unplugged the IAC AND THE engine drops rpm but remains running. It also returns to normal rpm when it is plugged back in.

Air filter is stock and clean.

When the truck does crank it runs normal with full power. Fuel mileage sucks but it always has.

Any ideas? Thanks

 

[yavapaires]

I guess I am lucky 96 4.0 OHV with 150k+ XLT Control Track 4x4.Runs around 20MPG, no real problems other than worn rocker arms and pushrods on right bank. Replaced rocker arms and push rods on left bank about 3k miles back. Starts every morning, and every time during the day, it ain't perfect, but seems to be a good vehicle. Have owned it for about 11months. You just have to realize they are what they are and treat them accordingly.

 

[koda2000]

failing crank sensor?

 

[Stick4503]

I guess I am lucky 96 4.0 OHV with 150k+ XLT Control Track 4x4.Runs around 20MPG, no real problems other than worn rocker arms and pushrods on right bank. Replaced rocker arms and push rods on left bank about 3k miles back. Starts every morning, and every time during the day, it ain't perfect, but seems to be a good vehicle. Have owned it for about 11months. You just have to realize they are what they are and treat them accordingly.

Glad to head yours is doing OK. This does not help my wife or son from getting stranded away from the house. Please no more stories just sugestions of what the problem may be.

Thanks

 

[Stick4503]

failing crank sensor?

You think so? Even with no fault codes? I will look up how to check this or try to replace it. I'm just trying not to go at this problem by installing parts until i find the one thats causing the problem. It gets quite pricey that way.

Thanks for your suggestion.

 

[Stick4503]

Mine is the same problem as user johnwartjr.

 

[yavapaires]

You think so? Even with no fault codes? I will look up how to check this or try to replace it. I'm just trying not to go at this problem by installing parts until i find the one thats causing the problem. It gets quite pricey that way.

Thanks for your suggestion.

It is possible the diagnostic port my be disconected, thus no fault codes. Look for : vacuum leaks, water in the intake, loose intake manifold bolts, bad PVC valve/ hose. I have not had this problem, nor known of anyone who has. So any suggestions are just that, suggestions.

 

[Stick4503]

anyone else. Please help.

 

[Stick4503]

On my situation above I have been told of a case before that involved a temperature sending unit going bad, causing the pcm to think that the engine is very cold after being ran and causing it to dump large amounts of fuel during the starting attempts. Causing a flooding type situation. During the starting attempts I do smell a strong fuel smell.

Any thoughts on if this sounds possible?

Best I can tell I have 2 sensors for temp. One is $10 the other is $20, so no big money loss if its not. Just want to hear what you all may think.

 

[Stick4503]

Anyone know if temp sensor can cause this?

 

[mobile848]

Sounds like maf/map problem to me those would throw a code though are you sure your check engine light works and if you are scanning it what kind of scanner cause the small hand scanners do not pick all codes up learned that from experience we have a modis at work that picks up codes that our small one doesn't see

 

[Stick4503]

Scanner OBD II from two auto parts stores.
Check engine light- yes it works, I unplugged the IAC Valve too long while checking it and check engine light came one and codes read correct for that.

Am I correct as to this engine only having 2 temp sensors?

Will check the mac/map in the morning.

 

[Stick4503]

Scanner OBD II from two auto parts stores.
Check engine light- yes it works, I unplugged the IAC Valve too long while checking it and check engine light came one and codes read correct for that.

Am I correct as to this engine only having 2 temp sensors?

Will check the mac/map in the morning.

 

[budwich]

I have battled a similar problem over the last couple of years on my 96. Starts fine when cold, actually surprising well. But if it has been run for a short period of time, 15-20 minutes or so, then sometimes a "restart" (after going in and out of a store say), it will start but run "badly". I thought it was a fuel pump issue as I run my tank "light" for various "reasons"... Anyways, one particular bad "restart", it threw some "misfire codes". I had changed the fuel filter in the past (previously) and it seemed to help a bit with less events.... but never any codes til this one time. Anyways, since the misfires were "directed" at a specific cylinder(s) (two), I thought it unlikely to be a fueling issue and more of a firing problem... checked the plugs... good, clean, gapped. Then moved on to the wires, original. Replaced them with new "non-name brands". The problem disappeared for about a year or so... until it got cool / cold. It was back in november... hhmmmmm :-( no codes but the same poor "restart" problem.... I am sure that if I hit the gas more than I should... kind of forcing it, I could probably cause a "code problem"... maybe. Anyways, no codes, after check wiring / plugs, I moved on to the IAC. Pulled it and cleaned... lots of "crud" during cleaning. Back in and been better / good ever since.

Sorry for the long story... its been a long "investigation" as it doesn't always rear its head up. Anyways, my suggestion would be check / change plugs, check / change wires (how old are yours), and then clean IAC thoroughly (replace maybe). Good "hunting".

 

[Stick4503]

Ok, changed out both temp sensors and.it seems like maybe the problem is a little better. It still gives trouble starting when warm or hot. But it does not seem to take as many times to get it started. Cleaned the maf with.some brake cleaner not sure if.thjs has helped yet,have not gone anywhere yet. What am I.missing. I have got.to get this thing dependable for.my wife and.teen.son. anymore ideas.

 

[bobflood]

Ok, changed out both temp sensors and.it seems like maybe the problem is a little better. It still gives trouble starting when warm or hot. But it does not seem to take as many times to get it started. Cleaned the maf with.some brake cleaner not sure if.thjs has helped yet,have not gone anywhere yet. What am I.missing. I have got.to get this thing dependable for.my wife and.teen.son. anymore ideas.

Temp sensor was very possibly a problem; one drives the guage and the other goes to the PCM - the PCM one would affect starting when warm. Should never use anything but MAF cleaner or electronic cleaner on the MAF. MAF issues more often show up as driveability rather than starting problems. If the temp sensor didn't do it, a failing crank position sensor is also a possibility.

 

[Stick4503]

Temp sensor was very possibly a problem; one drives the guage and the other goes to the PCM - the PCM one would affect starting when warm. Should never use anything but MAF cleaner or electronic cleaner on the MAF. MAF issues more often show up as driveability rather than starting problems. If the temp sensor didn't do it, a failing crank position sensor is also a possibility.

I checked the crank position sensor the other day but it was getting dark so i have not pulled it yet for test. The sensor did have a lot of build up between it and the external crank end. I used a piece of plastic to clean it a little but it needs to be pulled, tested and cleaned at best.

Thanks for the input.

 

[Stick4503]

I checked the crank position sensor the other day but it was getting dark so i have not pulled it yet for test. The sensor did have a lot of build up between it and the external crank end. I used a piece of plastic to clean it a little but it needs to be pulled, tested and cleaned at best.

Thanks for the input.

O.K. I checked the crank position sensor today with a volt meter and I seem to get the correct resistance with the ohm setting. I set the meter to AC and I get a reading, can’t see a fluctuation as the manual says but do get a reading.

I am still having my original hot start problem, however it seems to be easier to crank. Does not take as many times and easier to get the gas pressed just right. It also seems to not happen as often.

What else can cause a hard start when the engine is hot? I have found a few posts similar to mine but no one ever posted what if any results they have had.

Any ideas? Please.

 

[Turdle]

Got a hunch here--so bear with me.

Next time you get a hot start problem, switch the key on and off 4 times, then try a restart. See if this works. If so, it indicates low fuel volume-pressure

 

[Stick4503]

I will give it a try. I am looking for a fuel pressure gauge I can rent or borrow that has not been beat to hell. I got one from AutoZone and it had so many small parts missing I could never get a reading from it.