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Discussion Starter #1
56reg mk2 1.6petrol zetec climate pack. 54000k on the clock.

Ok, it started off where every few months the car would not start after being driven and left for 20minutes or so, and I come back and I would not start. . Now the problem has gotten really bad, I have to pump the accelerator whilst cranking the engine to get it started (cold/warm) it doesn't matter what the engine temp is. It shows nothing on diagnostic tests.

I've had a fuel pressure test which when the problem was only once a month and the pressure dropped dramatically.

I've had new plugs
New crank sensor
New cam sensor
New fuel pump.

The car does not misfire and it runs perfect once started. Idles between 1100k when cold and 900k when warm. The car runs absolute spot on.

Has anyone had the same problem or known about this before.
 

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Old Phart
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44,596 Posts
Has anyone checked the fuel injectors? One or more could drip & make it hard to start.

Holding the pedal down when starting works to clear a flooded engine, if that works to start it you would have another symptom pointing to that guess.

Partially warm is the hardest condition for starting, not a cold start or a warm start so the temp sensors need to be accurate. Did anyone look at those numbers to see if they make sense when partially warm? Any "Mods" like a different intake?

This will be moved to "General Tech Chat" for more answers when a "Mod" is avail. to do that, best place here for answers to general mechanical issues.

Welcome!
 

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Captain TMI
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It sounds like a bad fuel sensor to me, but it could be a bad fuel pump controller also. The problem with this is that most mechanics don't know how to test this stuff. We don't even know how to test it. I would actually think it was the fuel pump controller first- however, there is always the fuel cut-off switch that you can test easily. You can bypass the fuel cutoff switch in case it is the problem. You simply bridge the two pins on the fuel cutoff switch connector. There's a 1% chance that is it, but it costs nothing to bypass it and see if that solves the issue. If it does solve the issue, then replace it immediately- do not drive around with the switch bypassed. If you get in an accident, the fuel pump will continue to pump fuel which could compound the accident.
 

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Has anyone checked the fuel injectors? One or more could drip & make it hard to start.

Holding the pedal down when starting works to clear a flooded engine, if that works to start it you would have another symptom pointing to that guess.
Although the odometer seems low, this was my first thought. A leaking injector. Does the problem happen at every start? You can take out stuff (not sure on your car) to get access to the fuel pump plug. Next time you're ready to shut the engine off, unplug the fuel pump instead. Let it die due to fuel starvation. Then shut off ignition. This will depressurize the fuel system. Later, when you're ready to drive again, plug in the fuel pump and start the car the usual way. If the problem was leaking injectors, the car should start fine. Good luck. (Background: 86-91 Mazda RX-7's tend to flood easily with leaking injectors - some add fuel pump cutoff switches instead of replacing injectors or having them rebuilt/reman.)

It sounds like a bad fuel sensor to me, but it could be a bad fuel pump controller also. ....there is always the fuel cut-off switch that you can test easily. ..
I'm not sure what a fuel sensor or controller is, but thought about the fuel pump shutoff. But the rest of OP's description seems this is unlikely, unless it's kind of just making a bad connection...but still.

edit: fuel pumps are usually just controlled via relays and either get juice or not...But...not every pump is controlled like this. I've heard of a controller that varies the voltage to the fuel pump...it's possible at warm engine temps. the fuel pump may require less voltage, but one would have to check into this more in-depth. FSM not here at work :(
 

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Old Phart
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"pumping throttle to start" and "pressure drops rapidly" were the clues that lead me to the injector possibility. Fuel pump assembly replaced should take care of a check valve issue.

Our fuel pumps aren't constant on when running, it's a returnless system controlled by a variable electrical input to the pump to maintain proper pressure - monitored by the pressure sensor whynot mentioned.
 

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Old Phart
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Thought I'd clarify the "why" for my guess, might not be the answer but it fits the known symptoms & is a mechanical fault that wouldn't show up on any of the "scans" mentioned. Matches your experience & another I've seen recently.

I'm MUCH better acquainted with return type fuel systems controlled by relay & pressure regulator. Simpler to understand & diagnose than the computer controlled returnless system. This is better for performance & emissions though, you're not returning warm fuel to the tank so the fuel stays cooler & less vapor is produced.
 

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Discussion Starter #10
Hi sorry for late reply..

Got my car back today. Changed crank sensor again and the cam, it seemed to start great at first untill I took it home. I left it for 30minutes, went to start and it just kept cranking and trying it's very best untill the engine started shaking wildly.

So after driving it and getting it stated a few times I finally got an engine check light on the dash, put OBD2 reader in and I get the coat p1071

Does anyone think it may be the MAF sensir? Although once the car has started it idles and drives so smoothly. It's a starting issue and that is all I believe. To much or to little air?

Also I found rust in the spark plug wells and up the inside of the CORE HT LEADS.
 

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Discussion Starter #11
Hi sorry for late reply..

Got my car back today. Changed crank sensor again and the cam, it seemed to start great at first untill I took it home. I left it for 30minutes, went to start and it just kept cranking and trying it's very best untill the engine started shaking wildly.

So after driving it and getting it stated a few times I finally got an engine check light on the dash, put OBD2 reader in and I get the coat p1071

Does anyone think it may be the MAF sensir? Although once the car has started it idles and drives so smoothly. It's a starting issue and that is all I believe. To much or to little air?

Also I found rust in the spark plug wells and up the inside of the CORE HT LEADS.
 

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Old Phart
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Didn't find a listing for code 1071, might want to recheck that.

Rusty plugs/wires are from prev. water down the holes, engine washing is the most common cause.
 

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Discussion Starter #14
Since I got the car back I have noticed a new sound from my exhaust, can't really explain it it's blowing out un evenly sort of if it has a hole in but only when idling. MAYBE THAT GOVES A BETTER CLUE :)
 

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Old Phart
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0171 has a long list of possible causes, but with the mentioned exh. leak you need to check if that is near or before the O2 sensor - that would give a "false" code.
 
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