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Discussion Starter #1
Hi everybody, hoping you can help me with my 03 svt. The car cranks but wont start. It wouldn't start for a couple days then it started for 2 days when it was warmer out, when it did start it had an erratic idle and was running super rich. Now it hasn't started again for 2 days. It cranks, has good spark, the fuel pump primes, and the spark plugs are soaked in gas. Has good compression. Also the timing belt is good. Only CEL I have is for the low speed fan. Help!! Thanks
 

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Moved to General Tech Chat.

Other than air filter/airbox plugged up (you DID check, right?) you might start by checking the fuel pressure sensor reference hose from the sensor to the intake for gas. Any fuel in there means the sensor is bad & leaking fuel into the intake.
 

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Discussion Starter #3
There is no fuel coming out of the frps. Ive have now gotten it to start twice by unplugging the maf. I think the iat is causing it to flood on cold start. Have anyone seen this happen before?
 

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It may just be starting from sitting and have nothing to do with the MAF. Fuel soaked plugs often do that if the sequence makes any sense there. Soaked plugs short out across the porcelain to not start, they have to be bone dry to stop that.

The cars run rich at cold start anyway, the FI programming makes like old school choke. Proper engine condition handles that fine. Marginal plugs will blow all that out of the water though.
 

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any codes? check you inerta switch if your not getting fuel and check your crank sensor becasue it can do some really funny stuff.. when mine went out it would not want to start sometimes id have fuel sometimes it cut out on me while driving that crank sensor can cause really weird things
 

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Discussion Starter #6
No dtc and checked the inertia switch and it was ok. I like the crank sensor idea. The scan tool shows engine rpm but i suppose it xould stilll be messed uo
 

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If you've got that scan tool handy you can check your guess on the IAT easily. Just see if it makes sense vs. outside air temps (won't be identical).
 

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It wouldn't run at all if it weren't getting any crank position signal, I don't think the PCM/ECU wouldn't even attempt to send spark timing without that and you wouldn't have spark. TMK that's the one truly essential sensor for a running (zetec) engine, the rest can be "guessed" by learned previous data, such as TPS or IAT in comparison to MAF readings. It wouldn't run great without the rest, but it would run.

I've had a similar problem to yours (lived in WI until recently) and once it absolutely cleared up after unplugging the MAF harness. I just checked and there are at least two and maybe three sensors integrated into the MAF housing, definitely the MAF sensor itself and the IAT sensor separately. One of those probably uses two separate resistors for a signal, cause I can't think what, if any, a third sensor could possibly be.

I would unplug the battery for a good while for so the PCM loses it's "learned data", pull the MAF sensor housing, and very carefully (with a q tip and electronics cleaner) make sure those resistors and wiring are squeaky clean.

I can tell you how to test, with a voltmeter, some known good signal voltages and you can compare it to what you're seeing, but you need an automotive grade
multimeter, alligator clips and regular small paper clips and some familiarity with "backprobing" to at least somewhat interpret what those sensors are reading key on/ engine off and idling/running. I'll probably get some known good values later just for the practice and maybe see if there is a third sensor in there.

tl;dr : I'd investigate the MAF sensor further
 

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Discussion Starter #9
Well i replaced the maf and the consistently starts now although sometimes somewhat labored. But it runs like crap and is now throwing a p1381 cam code. Car seems super rich and wont idle when warm. It has no power.There is no slack in the belt and it hasn't be replaced recently to the best of my knowledge. What should my next step be?
 

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Discussion Starter #10
I spent some time today resetting the timing with the ford tools. When the car started it ran great, but that
only lasted on trip and now its throwing the p1381 code again and running like crap. Any ideas?
 

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i am not going to trust your opinion on the timing belt looking good. Instead, I would plan on getting it replaced as this sounds what the problem is with your car.

also, if for some reason your timing is actually still good I would look at the crank position sensor to ensure that it is not physically damaged
 

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Op says timing belt is 'good' and then he has 'reset' the timing but not any mention of a new belt there. You ABSOLUTELY CANNOT just look at a toothed timing belt and determine it is good by simply viewing it. If an old one it is most likely jumping teeth and if an SVT OP is right on the edge of bending valves bigtime.
 

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Ouch

Yeah, can't re-use a belt that way - tensioner won't set right on a used belt for one issue alone.

Playing with fire on a car that can bend valves if timing jumps too far/belt strips or breaks.
 

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I think you're almost there and you sound like a smart guy. Like others have said, you need to be damn sure your timing components are good to go, whether it be brand new or not. You've already reset the base timing once without catastrophe and you can do that again.

Check this thread and read it comprehensively, I think your VCT solenoid/gear may have not been in the correct "at rest" position (IIRC fully rotated towards windshield) when you locked in the base timing.

Maybe do it all to be on the safe side, new timing components, new engine oil (VCT is engine oil pressure operated and can catch debris and screw up)

but read the thread, I didn't but I'm sure your answer is in there.

Best of luck man. Think hard on it.

Edit: and again, the engine wouldn't run at all without a steady/solid CPS signal. You can basically disregard that possibility right now.
 
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