Good feedback & to hear you believe you got a positive on your troubleshooting check & think the new fuel pump power relay has put the fix on your intermittent no start problem.

Those pesky power relays are a common problem part on intermittent no power circuit fits, so much so that some folks carry spares in the glove box with their fuses!!!!

Don't know about you though, Greg goes to the gas station to get donuts, so I suppose that means you go to the donut shop to get gas & "thump" on your truck to fix it!!!! Hey, what ever works!!!! lol

 

PawPaw, u r da funniest man on the internet!

 

my truck has been having problems starting from time to time and I thought that maybe this would work for me. I tried a different relay but it didn't help any. I normally crank the starter for 3 secs, and nothing. I do it a second time for 3 secs, and at the very end of that crank the oil pressure will start to read and it almost cranks over. The 3rd time the oil pressure reads as soon as its on and then the truck cranks right over in less then a second. If I crank it for 4-5 secs the 2nd time it will often start, but then the abs warning light stays on. Could it be a different relay dealing with the oil?

 

bump for my most recent post. Anyone that can help?

 

What happens if you just go from OFF to KOEO (until you hear the fuel pump stop each time) & do this in succession two or three times (but don't crank the engine), THEN immediately crank the engine after the third or fourth Off to KOEO cycle, will it then catch & run without delay????

If so, before one of it's no start fits, attach a fuel pressure gauge to the fuel rail schrader valve, for a fuel pressure test on the first OFF to KOEO try & then post the FP number you get.

If it's low, maybe suspect a lazy pump, or faulty FP regulator.

 

I have tried that and it doesn't seem to matter if I do the key on-off a couple times or not. The truck runs great otherwise with 125k on the odometer but this is going to wear the starter out pretty quick.

Like I said it seems more relate to the oil pressure. The first time it shows no pressure, the second time at the very end it will start to jump up and down. And the third time it kicks as soon as the starter is on and then it cranks over. I started to notice this last summer for the first time and then it went away when it got cooler. I live in phoenix and in the summer they use a different mix of gas to help the smog and I suspected then that it might have had something to do with the gas......

I have been considering replacing the coil/rotor/cap and checking the plugs as I think it is the stock rotor and its been a while since I did the plugs. Not sure how that would effect oil pressure.

Does your show pressure as soon as it starts cranking?

 

You may have more than one problem & it sounds like you might be behind the scheduled maintenance curve.

Yup spark plugs, rotor & fuel recipe don't have anything to do with oil pressure, but with your mileage, the viscosity of the oil your using in summer might, the condition of the oil pump, it's screen, the oil filter your using, & maybe the oil pressure sending unit, if the computer is also using it to detect oil pressure, along with output from the crank sensor for spark & the cam sensor for fuel injector timing on a start.

So right now I'm not sure about just how your year/model is wired, maybe an electrical wiring guru on your model will chime in.

If it uses the oil pressure sensor to close the start/run loop, then a faulty op sensor, or some kind of oil pressure build problem, could cause a start/run delay problem.

I believe these vehicles only use the oil pressure switch to operate the oil pressure gauge, which the way Ford has them wired now, the oil pressure gauge is just like a mechanical idiot light, as it'll read mid range if we have about 7psi or more oil pressure.

So knowing that, it seems that & from your description of how the OP gauge behaves when cranking the engine on a start, it seems your oil pump is taking a long time to build even that much oil pressure, so all that brought about the above questions concerning the oil filter, viscosity, clogged up pick up screen & worn pump ideas.

So we still have a bunch of questions to resolve before narrowing down your delayed start problem. It could be one, some, or a combination of things yet undetermined.

So begin with the basics, make sure you have in spec fuel pressure at the first KOEO & post the numbers.

Then make sure you have spark when cranking the engine.

If the cap & rotor are OEM, their gap is likely excessive & could cause a weak spark & hard start, as the battery voltage is likely to be low from cranking the engine, so everything in the fuel & ignition system needs to be in good shape to get er running on a start.

So that means you need to know the battery will pass a load test too!!!!
So maybe have the battery load tested, most autoparts stores will do this at no charge.

Check the fuel pressure as I've suggested.

Then disable the fuel pump so the engine won't run, remove the oil pressure sender & install a mechanical, shop oil pressure gauge & monitor the oil pressure when cranking.

By then you should have some idea whats going on with your delayed start.

What viscosity oil & what brand oil filter are you using?

A whole bunch of thoughts for consideration.

 

wow, too much to answer there...... let me see if I can go one at a time.

I am not a motor person so please bear with me... I have never messed with the fuel rail to know how to test the pressure there. I will check my haynes manual to see it has anything there, I don't have a gauge either.

To check for spark while cranking I assume I will need to pull a plug and see or is there an easier way?

As I said I can't remember the last time I changed the plugs or if I ever did the rotor and cap so they are due(maybe this weekend) and while it is out I will check for spark under cranking.

I replaced the alt and battery last year and upgraded all the cables to them so I know the power shtuff should be ok.

I always check my manual in the parking lot of autozone to see what oil it recomends, I can never remember between my ranger and mustang. I know it is a high milage sythetic, nothing cheap....

I guess I will have to look into getting an oil pressure gauge and a fuel pressure gauge, or see if any of my wrenching buddies have one.....

 

Ok good feedback.

Well sounds like we can put the battery question aside.

Maybe a clogged up oil pump screen too, if you've been using synthetic oil & the specified vscosity in your owners manul, as it's likely to be able to take the heat in the hot SW.

What oil filter are you using????
A clogged up, or wrong design, or one with a faulty anit-drainback valve, could cause some strange things to happen with oil pressure on a start.

So don't worry about an oil pressure gauge hook up & pressure check just yet.

DON'T, crank the engine with the igntion high voltage section open, use an inductive type timing light to check for spark. You likely have spark, as it'll eventually run, but it may be weak from excessive gap in the cap/rotor & plugs because of wear & or bad plug wires.

Most autopars stores have the tools you need to check for spark & fuel pressure, in their "Loan-A-Tool" program, for a refundable deposit.

So a timing light to safely check for spark & a fuel pressure gauge that properly fits the fuel rail schrader valve to check for fuel pressure, would tell you which is absent, or out of spec when you first try to start.

To hook up the fuel pressure gauge, relieve fuel pressure by disabling the fuel pump & cranking the engine until it stops trying to start.
You can disable the pump by tripping or unpluging the in cabin inertia switch.

Sounds like you are behind on past & present due scheduled maintenance items, so if you've ignored the ignition system I'll bet the fuel filter hasn't been changed on time either & that could be in play with fuel pressure.

If the cap, rotor, plugs & wires haven't been changed, I agree they probably should be with the mileage they have on them.

While your at it the O2 sensors switching speed probably should be checked, as old ones with 75-100K miles are usually getting lazy/slow switching speed by then, sorta like pawpaw!!!! lol
So if you could come by a scantool with cables that'll hook up to your OBD-1 system diagnostic connector, that'll read their PID output to the computer, you could easily check them, while monitoring other sensor PID's when it's acting out, or running & all that info could simplify & shorten your trouble shoot.

Anyway call around & see what the different stores have in their loan program that you need & have at your trouble shoot.

 

thanks for all the help, feels like we are getting somewhere.

We can rule out the fuel filter as I know I have replaced it 2 times myself as recently as last year(didn't help then).

Thanks for the info on the tools I will check that out. Being unemployed ever little bit helps.

I have a buddy that wants to replace the rotor and plugs on his mustang and offered to help him help me help him ect....

One other possibility is that I know I had the usual leaky fuel filler neck a couple of years ago. My mechanic couldn't find any replacement and ended up rigging it. I keep track of my milage and nothing has ever dropped and the check engine light that was on for the leaky tank has stayed off.

Today I am workin on a trailer hitch for the truck(pending move back cross country) and will be making a trip to the autoparts store for a trailer harness and will see about the tools and check on the price of hte rotor/cap/plugs.

Thanks again, I would like to get this solved before I take off back to the midwest. Its 1700 miles..........

 

I'm having the same problem with my 1994 4 Cyl Ranger. It's been going on for 2 years now and I'm surprised I've not worn out my starter. I've replaced so many parts already - the coils, the O2 sensor, the crank sensor, the Ignition starter, nothing has worked. It almost always starts cold, but won't start, or rough start with ck engine light, after hot. No codes thrown. Dealer said they tested the fuel pressure, cleaned the throttle body, they could never figure it out after 3 tries. Haven't tried AIC, also read that the temp control sensor could be bad, or fuel pump going out - but if fuel pump was issue, why does it run great once started? One mechanic said computer was bad. Please help - can't afford a new truck now.