96 v8 starting issue

[bigcrunch]

Hi, my 96 V8 has sporatic starting issues when warmed up or cold.
Sometimes it gets no fire, other times is sputters hits on a couple of cylinders then dies.
I have replaced the crank position sensor with a BWD unit and fresh spark plugs.
Still happens any suggestions?

thanks and great site....

 

[bigcrunch]

also no check engine light or codes.

 

[shadowless127]

have u checked the coil packs?

 

[robertoa1a]

Check the fuel pressure if you can. What I mean by that is, when a fuel pump goes bad It can be intermittant so you would need to catch it at one of its bad points. Not so easy! It may take 50 tries. You need a key on/off friend to help.

 

[williams.cory]

dirty IAC??? how does it idle when warm?

 

[bigcrunch]

Has newer Accel coil packs.

New IAC installed today, warranty swap at Advance.

Fuel pump check, did it about 100 times today.
Started it had fuel pressure gauge hooked up 30 psi every time, shut it off if pressure stayed about 30 it started no problem.
When it bleed down to 0 in about 60 seconds no start.

real pain in the ***

 

[williams.cory]

plugged air filter? Dirty mass air flow sensor??

 

[robertoa1a]

Possibility, and a long shot;

The '96 was the first year of the true OBDII system on explorers. The tank is the same as the former explorers (no baffles inside). The factory disabled CEL codes from being read from the evap system because when fuel sloshed around while hard cornering, it would throw false codes.

This means that you may have an evap related problem if all other problems have been addressed.

There is a purge canister above the spare tire where evaporative emissions are sent. There is a common problem with the valve up there. After the evap goes in the canister it is purged into the intake. There is also a valve under the battery.

A problem with the valve will make it seem like there is a huge vacuum leak on start up.

Can you further explain the starting behavior and what parts are checking good?

 

[williams.cory]

whens the last time the fuel filter was replaced? Might have a dirty fuel tank, crap in the bottom chocking the fuel pump. To check, disconnect fuel line before fuel filter, run line to a bottle/container, cycle key a couple times and see how clean the fuel is....

 

[bigcrunch]

fuel filter prob never, the fuel pump was replaced 1 year ago.

 

[bigcrunch]

plugged air filter? Dirty mass air flow sensor??

Filter I cleaned today also did not need it.

How does one determine a dirty mass air flow sensor? carbon build up? exactly where is it?

 

[williams.cory]

fuel filter prob never, the fuel pump was replaced 1 year ago.

Definetly replace the filter!!! That is probably why you are having problems. After sitting for a while, all the fuel drains out of the lines and when you go to start the pump cant prime the systems if you have a plugged filter....see if it will start like normal after cycling the key on and off 5-6 times....if it does then its definetly something plugged up

 

[bigcrunch]

Possibility, and a long shot;

The '96 was the first year of the true OBDII system on explorers. The tank is the same as the former explorers (no baffles inside). The factory disabled CEL codes from being read from the evap system because when fuel sloshed around while hard cornering, it would throw false codes.

This means that you may have an evap related problem if all other problems have been addressed.

There is a purge canister above the spare tire where evaporative emissions are sent. There is a common problem with the valve up there. After the evap goes in the canister it is purged into the intake. There is also a valve under the battery.

A problem with the valve will make it seem like there is a huge vacuum leak on start up.

Can you further explain the starting behavior and what parts are checking good?

This explorer was built in 1995, first of the V8s.

What does the canister look like also the valve under the battery? how is that repaired if that is the case?

I replaced the crank position sensor on Wednesday, the IAC again today.
check the vacuum hoses that I could access to check for cracks.
Check the fuel pressure at the injector rail.

When I start it, sometimes it starts when engine is cold or warm.
Then every so often no start cold or warm engine, what it does just spins over. Then when it does hit it is on a rough idle at very low RPM, about 200, I can feather the throttle and sometimes it goes to normal idle, sometimes it dies.



First time my beloved explorer did this was in the middle of Kansas 2 am after filling up with gas, in a very sparcely populated area.

 

[bigcrunch]

Definetly replace the filter!!! That is probably why you are having problems. After sitting for a while, all the fuel drains out of the lines and when you go to start the pump cant prime the systems if you have a plugged filter....see if it will start like normal after cycling the key on and off 5-6 times....if it does then its definetly something plugged up

I was trying to look into maybe a check valve or something similar on the feed line, but no info to that.

I'll try a fuel filter, whats 10.99 for a quality (WIX) one.

 

[bigcrunch]

Anyone using a Purolator fuel filter? succesfully?


http://shop.advanceautoparts.com/we...y=0&pageSize=20&filters=part_type:Fuel+Filter

 

[bigcrunch]

Definetly replace the filter!!! That is probably why you are having problems. After sitting for a while, all the fuel drains out of the lines and when you go to start the pump cant prime the systems if you have a plugged filter....see if it will start like normal after cycling the key on and off 5-6 times....if it does then its definetly something plugged up

I have 30 psi at idle, even with a clogged fuel filter???


still pulls real good during acceleration also,,, just thinking no leaning


thanks!!!!!!!!!!!!!!!!!!!!!!

 

[williams.cory]

Anyone using a Purolator fuel filter? succesfully?


http://shop.advanceautoparts.com/we...y=0&pageSize=20&filters=part_type:Fuel+Filter

they all work fine, I guess. I put a fram on mine....works good. MAF sensor is the only pther sensor beside the IAC valve, its loated right by the IAC. If I remember right, to get the sensor out you need to undo 2 safety torx bolts, special fittings...So take out the whole intake, use a can of special MAF sensor cleaning stuff, and give the sensor good long sprays. Let dry before installing. Do that and replace the fuel filter and hopefully the problem will be fixed.

 

[williams.cory]

I have 30 psi at idle, even with a clogged fuel filter???


still pulls real good during acceleration also,,, just thinking no leaning


thanks!!!!!!!!!!!!!!!!!!!!!!

I'm thinking that if you do have a clogged filter, after all the pressure is lost in the line after turning the engine off, the pump cant prime the lines enough to keep it idling smooth or stay running when you start it. Just a thought.....

What happens when you cycle the key 5-6 times and then try to start? Try the simple and easy stuff first, and then get more involved in the situation.

 

[bigcrunch]

Will MAF sensor issues give a trouble code?

 

[williams.cory]

Will MAF sensor issues give a trouble code?

I dont believe so, not unless the sensor isnt working or is broken. as long as the computer is getting a reading from it.....someone correct me if im wrong.....