No Start Please Help 4.0 OHV | Ford Explorer Forums - Serious Explorations

  • Register Today It's free!

No Start Please Help 4.0 OHV

Shanemm

New Member
Joined
July 12, 2016
Messages
7
Reaction score
0
Location
California
City, State
Salinas ca
Year, Model & Trim Level
1997 4.0 sport
I've been dealing with these issues for going on two months now. The problems originally started when I was getting excessive EGR flow. I replaced the valve the sensor and the solenoid. The car always started just ran really rough. After I changed the parts the car refuses to start at all, just cranks and cranks and cranks. I had an engine disabled code, checked the inertia switch which was still down, reprogrammed my keys into PATS and still no start. I checked the Fuel pump relay and fuse and they are good. I'm at wits end about to just tow it. If there is any advice someone can give me I would greatly appreciate it. I have Forscan and obd 2. The only thing I can think of is something in the fuel system now, but it was working fine before. It all started after I had the battery disconnected for a day. Before it would still start and just run horribly.

Thanks for taking the time to read this
 






Well you need Fuel and spark to start. Assuming PATS is good (I think there is a led that gives status)
1) How is fuel pressure?
2)How is the crank signal. Not sure if Forscan can monitor crank RPM or as you try to start the engine. That will test the Crank sensor.

Other things to look for:
Check engine light comes on when you turn the key? (Tests that the PCM is getting power).
Try starting with the gas pedal depressed a bit (check IAC).
Try disconnecting the battery. There may be a learned strategy because of the issue that is preventing it from starting. (long shot)
Sure everything is tight after all that EGR work? No vac leaks??
 






Well you need Fuel and spark to start. Assuming PATS is good (I think there is a led that gives status)
1) How is fuel pressure?
2)How is the crank signal. Not sure if Forscan can monitor crank RPM or as you try to start thpcm e engine. That will test the Crank sensor.

Other things to look for:
Check engine light comes on when you turn the key? (Tests that the PCM is getting power).pcm
Try starting with the gas pedal depressed a bit (check IAC).
Try disconnecting the battery. There may be a learned strategy because of the issue that is preventing it from starting. (long shot)
Sure everything is tight after all that EGR work? No vac leaks??
i'll check the fuel pressure tomorrow, I definitely don't know about the the crank RPM but will try to figure that out, though the cranking doesn't sound slow it sounds good shaking the car and all trying it's hardest to turn. The only codes from the CEL I've had was from the excess egr and the pats. The battery was disconnected for five days as of this last round about, had to recharge it. As far as vac leaks there weren't any I could tell before hand and everything with the EGR is tight as can be, when I crank the retaining nut on the EGR valve it pretty much moves the whole block with tube. I don't think I could tighten it anymore to make a difference as I've read others have just hand tightened it and it worked just fine. Ive cranked down on it to make sure. Everything short of adding pipe dope to the mix. As far as before the issue I checked all the vacuum lines and they seemed still flexible, none fragile and hard I could never hear a leak. I thought about the PCM but it honestly seems okay it read the new key I put in as a theft and has been pulling all the codes just fine low voltage, egr, and PATS just fine. The car starts for a second if I disconnect the EGR hose off the top of the valve. Which I've replaced twice since this started as well as the dpfe. The solenoid was the last thing and only thing I havent re-replaced but that was already after these issues got to their worst. I'm at a lost here unless the pump decided to give out at the exact time I replaced all these. which I'm not completely ruling out but just seems highly unlikely.... Thank you for the response I really appreciate it
 






the egr valves and solenoids are not really a failure item, but the DPFE is (especially metal ones).

Go into forscan and check the DPFE pid. I believe it should be 1 volt or less if the engine isn't running. I'm thinking maybe a wiring issue? But if you plug the egr valve hose you basically eliminate the system. If the new egr valve seals, you are good to go. There is no egr at idle so it should run fine and set a code silently when you drive. Egr should be diagnosed with a scan tool or DVM and a vacuum pump when running. Also, fuel trims should be noted. When you throw parts you could miss other issues, but that is part of learning.

loosen your IAC and try to start. It is very easy to do. then reconnect . Disconnect the MAF sensor, I believe it is in the airbox. try to start. A dirty MAF or failing MAF could simulate a large vacuum leak, worth a shot. Can't hurt to clean it.

beyond this - when was the last plug and wire change? fuel filter?
 






Back
Top