No Start

[Jennifer]

Have a 97 XLT that cranks, but won't start. Been ongoing, has gotten worse and now won't start at all. Used to have to turn on/off, on/off several times, hold in the crank position for awhile and eventually would fire up. Reading the previous threads ideas of fuel pump, fuel pump relay, crankshaft position sensor and also IAC stuck open or MAF sensor problems. Is there a way I can narrow down which could be the culprit? The truck has 160k miles, tuneup/wires not that old. Fuel filter could be old. Sorry so long.

 

[Alec]

If you have doubts about the fuel filter go ahead and replace that. Then see where you're at.

 

[Ray Lobato]

I don't think it's you fuel filter.
first check to see if you do in fact have spark. To do this just pull a plug wire out and with you hand insulated put the end of the plug wire next to some bare metal, then have someone crank the motor. If it spark across the wire to the metal then you have spark going to the plugs. Next check to see if you are getting gas to the engine. You can rent a fuel perssure gauge from some auto parts store. The Chiltons manual can show you how to check it and what perssure it should be. A bad MAF won't keep your truck from starting, but it will make it run really bad.

 

[Jennifer]

Ok, swapped out the fuel pump relay with the WOT relay and no change, so I assume I can rule out the relay as a problem. Guess I can rule out the MAF sensor because once it used to start it ran fine. I will check for spark and hopefully be able to check for fuel pressure. If the pressure is up to what I not sure, but that would rule out the fuel pump I imagine? I really hate taking to a shop, they rip you off! Errr!

 

[Xplor]

Jennifer, you may want to go to AutoZone and get those sensors you mention tested. I am in Jax also. It's sorta hard to pinpoint the issue.

 

[Jennifer]

Ok, found on an old thread that not only is the fuel pump relay a possibility, but also the PCM relay ties into the system so I went out and exchanged the PCM relay with the A/C WOT relay and after 3 cranks it started. I shut off and tried again and it started right up. I think swapping relays was lucky, not necessarily the problem and correct fix. Guess I will go get two new relays and replace, maybe also replace the crankshaft sensor if I can locate it, someone said the part was only about $30. I don't know. Really don't want to go waste my time and money at a garage. You guys on this site helped fix my 4wd indicator light (contacts on the motor dirty) vs a dealer wanting to most likely replace the entire motor for $600, I have confidence in you all again. Thanks for your help.

 

[BillWms01]

Jennifer,

I feel your pain. I hate to pay someone $$, when I can do it.

Sounds like you may have already found the following thread on CPS. If not, here it is.

http://www.explorerforum.com/forums...462&highlight=now+AND+then+AND+wont+AND+start

This replacement solved my similiar problem. If you can change a spark plug, you can change the CPS.

Good luck.

 

[BLUZ]

This sounds to me like you are losing fuel pressure. There should be a check valve either in the pump or externally that will keep the fuel pressure high after you shut the car off. If it goes bad then you those first few seconds of cranking are just repressuring the line. It will only start after the pressure is high enough.

You can check it by putting a fuel gage on there and watching it after you shut the car off. If within a few minutes the pressure drops, that is the problem.

You can also test it by doing this, if it works this way in an X. Turn the key to the "ON" position, do not crank it. This will tell the fuel pump to pressurize. Then turn it back off and wait about 7-10 seconds because there is probably a relay on there. Turn it back to "ON". Repeat this about 3-5 times. Then crank it, if this helps you know that its a bad check valve.

 

[BLUZ]

http://www.twinturbo.net/net/viewmsg.aspx?forum=technical&msg_id=630087

Oh yeah, you can check this thread that I wrote up, eventhough it is not for the X, it may still be relevant.