[burlingamekay]

I apologize if this has been asked.

I have a 2001 focus se 2.0 ztec motor,

Well my car has been doing this jerking thing while I'm driving it cuts out then it's fine, sometimes it will stall out. Anyways after it's done jerking it smells really bad like sulffer. (I'm guessing it's my cat) while coming home yesterday it started jerking and just shut off left me on the side of the road and now it won't start, it wants to turn over but won't start. Fuel pump is ruled out , has anybody gone threw this ? And could this issue just be a clogged cat?

Thanks

 

[Thomas.White]

I apologize if this has been asked.

I have a 2001 focus se 2.0 ztec motor,

Well my car has been doing this jerking thing while I'm driving it cuts out then it's fine, sometimes it will stall out. Anyways after it's done jerking it smells really bad like sulffer. (I'm guessing it's my cat) while coming home yesterday it started jerking and just shut off left me on the side of the road and now it won't start, it wants to turn over but won't start. Fuel pump is ruled out , has anybody gone threw this ? And could this issue just be a clogged cat?

Thanks

Assuming you have fuel as stated (hope you checked pressure while under a load),

Most things that cause "jerky" operation are:

COP (Coil On Plug)
Wires
Plugs

Most things that prevent and engine from starting AND present with "Jerky Operation" are

CPS (Crank Shaft Position Sensor).

Rarely do CAT's clog unless the 02 Sensors and both (STFT) short tern and (LTFT) long term Fuel Trim are way out allowing excessive fuel down stream.

 

[Marde]

If you are interested in learning about exhaust restrictions, clogged cats, cat temperatures, cat failures, and O2 sensor behavior, please read and/or watch the videos at this website->http://www.ericthecarguy.com/faq/sol...issues?start=8

Based on some of your symptoms and that smell, it seems like you may have a bad/clogged cat.

Most cars with clogged cats usually show a gradual loss of power prior to getting fully clogged. You also might have more than just one problem. Did you notice the car being slugish in the days/weeks leading up to now?

Thomas (above) mentioned COP's but that is for a different engine type. Your car has a coil-pack. The coil-pack often fails (gets hairline cracks) and causes lots of performance and/or misfire problems.

Do you have/did you have a Check Engine Light (CEL) before the no-start?

Call around to friends or local car part stores. These stores often have a free tool loan program (deposit required). Loan a OBD scan tool. Easy to use and your car is not required to have the engine ON for the scan to work. Record any DTC's (codes) and tell us what you get.

 

[burlingamekay]

Yes I had a check engine light on before all this happened, it was for my downstream 02 sensor, was going to replace it then realized whoever replaced it last stripped the threads right into the cat. So I was planning on replacing the 02 sensor and cat. And then the car just died at 55mph going down the road. The car does have lack of power and would run funny, if I was to start it it would run then stall out, turn it back on it would run fine ,then as I stated above it would jerk and cut out as I'm driving when it wanted to

 

[Marde]

Also, like Thomas said, checking the health of the spark plugs is a good idea, is fairly easy, but you might need a trained-eye in order to see and determine if anything is not right.

Has your fuel filter ever been replaced?

In order to inspect the coil pack, you need to remove it and inspect it very close and carefully for any hairline cracks.

 

[burlingamekay]

Yes fuel pump/filter and spark plugs /wires are all recently replaced

 

[Marde]

...then realized whoever replaced it last stripped the threads right into the cat....

Yeah, O2 sensors are supposed to be tightened very little, very carefully.

Sounds like a "history" of cat/O2 sensor issues. Yikes! That O2 bung-hole is likely dead, somewhat un-repairable. Without proper diag, I can not encourage you to replace the cat. Also, it can be difficult and is an expensive part. Replacing a cat and not troubleshooting why it failed is foolish. A new cat could last a long time, but die early (again) because of a pre-existing condition.

If you are looking at a new cat, please note that many online retailers will offer much better prices than your local Ford dealership. There are some retailers here at FF that offer excellent prices too. Here is one ->
http://www.focusfanatics.com/forum/forumdisplay.php?f=81

 

[Thomas.White]

Thomas (above) mentioned COP's but that is for a different engine type. Your car has a coil-pack. The coil-pack often fails (gets hairline cracks) and causes lots of performance and/or misfire problems.

Do you have/did you have a Check Engine Light (CEL) before the no-start?

Call around to friends or local car part stores. These stores often have a free tool loan program (deposit required). Loan a OBD scan tool. Easy to use and your car is not required to have the engine ON for the scan to work. Record any DTC's (codes) and tell us what you get.

Marde is correct, My Bad! I was using as an example. And, he is correct in acquiring a scan tool for troubleshooting.

Your Car has a DIS/DES (Common Waste Spark Ignition). So, if one of the coils in the pack is bad, the opposing cylinder will also show a miss-fire. Using a test light connected to ground, remove the coil wires one by one and witness the distance the arch travels. A bad coil pack will be noticeable shorter than the others. This will also confirm spark. In your case 1-3 and 4-2are the WSI Firing sequence. Also drag the tip around the base to find a leak. The are notorious for shot life cycles.

You can back-probe the signal wire of an injector using a DVOM, Scope, or Test light (Not LED!) )and see if it's being commanded by the PCM. That would confirm Fuel delivery.

The Down Stream 02 Sensor not being installed is a bad thing. That needs to be fixed. The PCM adjusts fuel trim based on it's (and several other) sensors. Too much fuel causes carbon build up, too little causes heat. The sensors maintain a proper balance.

**If the 02 Sensor connector or wiring came in contact with the exhaust and melted, closing the circuit the car will not start. It assumes you have adequate fuel impulse and skips each injector activation cycle.

 

[Marde]

Your Car has a DIS/DES (Common Waste Spark Ignition). So, if one of the coils in the pack is bad, the opposing cylinder will also show a miss-fire.

I did not know about the DIS/DES stuff. However, most of the bad coil packs I have seen here do not fail in that fashion. The coil pack cracks and the results are a mixed bag of symptoms. I am sure that has happened, but I do not remember a Focus coil pack failing like that; i.e., where cly 1 & 3 lose spark. Makes sense tho.

You can back-probe the signal wire of an injector using a DVOM, Scope, or Test light (Not LED!) )and see if it's being commanded by the PCM. That would confirm Fuel delivery.

Seems like that only confirms injector is being commanded, but is not a good measure of fuel delivery.

The Down Stream 02 Sensor not being installed is a bad thing. That needs to be fixed. The PCM adjusts fuel trim based on it's (and several other) sensors. Too much fuel causes carbon build up, too little causes heat. The sensors maintain a proper balance.

**If the 02 Sensor connector or wiring came in contact with the exhaust and melted, closing the circuit the car will not start. It assumes you have adequate fuel impulse and skips each injector activation cycle.

I was taught here at FF that the downstream O2 is only used for monitoring cat efficiency.

Damaged, shorted wires could do lots of weird stuff -maybe- even a no-start (!??)... but I would hope the car is smart enough to allow the car to start if the wires were simply cut or the O2 fuse/s were blown. Lots of stories here about O2 sensor wires being burned, smashed, cut and then DTC's popped up. Sometimes the car stays in open-loop mode. I do not remember bad O2 wires causing a no-start. Honestly, my memory is pretty bad, so please take my comments lightly.

 

[focusmaniaczx3]

check out your coil pack...

have someone sit in the car and turn the key to try and crank the car. pull a spark plug boot off the coil pack and hold the end as close to the coil pack as you can and still see into the hole. you are looking for sparks to jump from the coil pack to the plug wire. check all 4 plug wires. if there are not sparks you have a bad coil. check the pigtail connector that plugs into the coil as well. that has been known to have issues.

also do not rule out the fuel pump even though it was just replaced. this sounds like it could just as easily be a fuel pump. i had a cat that was almost %100 blocked and my car never acted like that. remove the fuel cap and place your ear very close to the filler while someone turns the key from off to on. if you hear nothing from the filler spout your fuel pump is shot. since it was recently replaced it may still be under warranty or may just be a fuel pump relay or maybe a fuse or something. maybe even the fuel filter.

 

[Thomas.White]

That's a good point on the Injector's being commanded by the PCM and its relation to Fuel Delivery. I'm only assuming he has Fuel Pressure as he stated above "the Pump is good". And, I like to use a gauge to ensure its within specifications. A lot of people just listen and say "well that's working".

As for the 02 connectors... I had a crank / no start I chased on an 02 Explorer for over eight hours and changed the PCM because there was no communication between the scan tool and the PCM. No difference. I spoke with the customer and he said the only thing he had done was a transmission replacement / rebuild about 3 months prior. I put it on a lift and saw the connected fused to the exhaust. Removed, replaced ends, and all was good. BTW, there was a TSB on that connector to be captured with a zip tie. We charged the other dealership with the PCM cost. Otherwise, I would own one I had no use for.

Both 02 Sensors work in a closed loop EFI System. Based on parameters programmed into the start and warm strategy, together they adjust fuel trim based on AIT (air intake ) TPS (throttle position), IAT (intake air temperature), and MAP (Manifold Absolute Pressure)and fuel delivery. When you look at a closed loop (or open for that matter) everything is similar to a big air pump rather than an engine. There are just a few things on spark side, a few on the fuel side, but upwards of 10 sensors on the air & exhaust side of the systems that can cause a Tech to take Tylenol.

The ideal way to determine a "clogged" exhaust is to remove up-stream 02 Sensor and place a gauge attachment to the Bung and measure the Exhaust Back pressure while cranking (fuel relay removed).

The first thing I would try here would be coil, then CPS

 

[Marde]

Little time for chat. Awesome post Thomas.

Most Foci have NO schrader valve (or similar) for connecting an external fuel pressure gauge, so here is what I ended up doing-> see post #13 ->
http://www.focusfanatics.com/forum/showthread.php?t=476818&page=2

I also did an exhaust back-pressure test after buying an appropriate low pressure test gauge. Did not check pressure while only cranking engine though... here is a post on what I did-> see post #3 ->
http://www.focusfanatics.com/forum/showthread.php?t=476906

I did not know that our Foci use the downstream O2 for fuel trim calc. I will have to go back and learn/re-learn some more about this. No hit on you, but I have a policy to doubt or believe nothing until after I have read it from two different sources.

I hope you stick around FF; new FF members (including peeps like me) need and appreciate people with your car Tech experience. Cheers!

 

[amc49]

All kinds of things wrong here. Beginning with OP just driving and driving until he forces himself to walk, not the way to do things. Running with incomplete ignition may well have toasted the cat and good job there. Waste spark DOES weaken both sides of the loop there but often less effect on one side than the other. Problems can show in just one cylinder or both of a pair, I've seen it both ways. Downstream cat IS only used to monitor the cat, it has nothing to do with air/fuel mixture setting. Back probing the injector only says injector working and nothing else, if no pressure you still don't have fuel delivery. If your eyes are fast enough (they're not!) two of the coil outputs will show the spark jumping from plug wire to coil or backwards and what waste spark does. Fuel pump was changed but exactly WHAT got changed there?, the entire module must change; you can't just change pump only and think it will work, it'll do exactly what is said here. Or work sometimes and not others and eventually possibly a permanent quit. The only available pump, the late one, will not fit in early module like an '01 model. So, spill it. Just hearing the pump does not guarantee fuel pressure either and car won't start.

Sounds to me like OP should have done tuneup a while back, now gets to do it and no guarantee it fixes anything but must to weed out troubles. Clogged cat does not prevent starting-only good running, it will start up and then go to crap.

One day some of you people will figure out how leaving the cars running like crap for lack of plugs or plug wires will cost you 10X the amount when the cat craps out because you refuse to fix things, but my hopes are not high there. Oh well, at least the parts people will love you to death.

Maintenance done correctly you should never need a cat at all unless way deep into close to 200K miles and maybe not even then.

Pull plugs and if black or wet change them then go to wires, learn to test them (no more than 5K ohms per foot) or new wires. If you suspect cat then unbolt it at the manifold joint and start car with a gap there to test. Expect some noise. The car dying at 55 mph now can be your lack of tuneup, bad cat or timing belt just shed teeth. You didn't help yourself there at all.

 

[amc49]

'The ideal way to determine a "clogged" exhaust is to remove up-stream 02 Sensor and place a gauge attachment to the Bung and measure the Exhaust Back pressure while cranking (fuel relay removed).'

The only thing that will show is close to a 100% clogged cat, it will hardly show an effect at 50% or so but the engine will definitely not run right at 50%. If throttle not held wide open the test will reveal nothing, too small an amount of air coming through to even back pressure that small a hole. At true 100% clogged you should be getting some backfire through the intake, the exhaust has nowhere to go and pollutes the intake after it to then burn slow and the lack of route of escape then makes it go backwards. Seen it a few times.

I do NOT agree that the downstream O2 on these sets air/fuel, it stays pretty much constant if correct and moves very little. It begins to switch much more widely and frequently once cat loses efficiency and doing that would send the PCM crazy trying to tell the difference between the two outputs since one will follow the other (time vs. distance), if second one gets to full switching speed like front one there would be no way for PCM to sort that out and besides second one is never supposed to get like that. The second one shows a small bit of action at accel as vs. decel but that's about all. You can run car without it and car runs fine except you get the cat code then. People run cars without them here all the time. They are a backup to the front to tell PCM when to go to closed loop, and then after that PCM merely monitors the back output to compare to the front to tell if cat is working right. At some arbitrary point the two waveforms get close enough and PCM then sets the bad cat code.

 

[burlingamekay]

Ok as I stated above the spark plugs/wires are new along with the fuel filter/pump. The car has had a tune up .I bought the car out of desperation the ppl that had owned it didn't take care of it so now its all falling on me. the car has 212k it's old it's falling apart and needs to be junked . My husband checked and the car is getting fuel it wants to crank over but cant. My husband isn't a master tech so I figured I'd come on here and get some suggestions on what might be causing the car not to start that's all, no need to point fingers on who's to blame amc49

 

[burlingamekay]

Thank you to everyone who has helped

 

[Thomas.White]

Little time for chat. Awesome post Thomas.

Most Foci have NO schrader valve (or similar) for connecting an external fuel pressure gauge, so here is what I ended up doing-> see post #13 ->
http://www.focusfanatics.com/forum/showthread.php?t=476818&page=2

I also did an exhaust back-pressure test after buying an appropriate low pressure test gauge. Did not check pressure while only cranking engine though... here is a post on what I did-> see post #3 ->
http://www.focusfanatics.com/forum/showthread.php?t=476906

I did not know that our Foci use the downstream O2 for fuel trim calc. I will have to go back and learn/re-learn some more about this. No hit on you, but I have a policy to doubt or believe nothing until after I have read it from two different sources.

I hope you stick around FF; new FF members (including peeps like me) need and appreciate people with your car Tech experience. Cheers!

1. There is a Schrader valve for pressure relief / testing on the rail.
2. You can't get an appropriate reading while the engine is running to determine back pressure. The pressure will fluctuate due to heat and fuel delivery. I'm only quoting the FSM.
3. True the down stream 02 determines the effectiveness of the CAT. It does this by recording exhaust temperature by generating a reference voltage (the hotter, the higher). Now, the upstream 02 Sensor determines the fuel trip for optimum engine performance.

Now, consider this, the down stream 02 Sensor is bad and is sending a arbitrary reference voltage, so the signal to the PCM for reference voltage is a cold engine (just started), if this were only for the CAT and did not communicate parameters with the upstream sensor, the PCM would command the injectors to be on infinitively flooding the chamber to increase temperature to increase CAT temperature. You would have a MIL with numerous Codes for MAP, IAC, 02, IAT, and so on because all these would be outside permissible lo/hi programming.

So, the upstream controls the overall engine management for exhaust gas temperature and the down stream makes it happen when needed for emissions (programmed allowances) of which this vehicle has a wide range (02 and before). Beginning in about 2011 they have become a problem for us (especially the DPF's). We see a lot of vehicles and replace a lot of sensors because of the regulations which will continue into 2020 under the mandate. There are constant updated flash programs for the PCM's. ** The real sad thing about this is, when the customers cars go out of warranty they will be left holding the bag, or paying the Piper as it were.

Now having access to the FSM is a great help. However, I won't cut and paste the information here as its proprietary.

------------------------------------

As for the other comments with I do not.... The wonderful thing about science is weather you believe it or not..... its true.

-----------------------------------

The maintenance comments are spot on. The MIL illuminates for a reason. I would like to what the Europeans have included in their high-end vehicles for MIL's, they have two LED's, yellow / red. A yellow can be ignored for 50 or so miles, the Red indicates immediate service required.

----------------------------------
I guarantee I could diagnose this in about a half hour with a lab scope and scan tool. However, the internet doesn't allow that and most people don't have what I have.

 

[Marde]

Most Foci have NO schrader valve (or similar) for connecting an external fuel pressure gauge,

1. There is a Schrader valve for pressure relief / testing on the rail.

I have only worked on a few Foci. NONE of the Foci I have worked on had a fuel rail schrader valve. Someone here at FF told me there are a few models that have fuel rail schrader valves and I believe this is true, but I will stand by what I first said "Most Foci have NO schrader valve". Not sure about MK-III models...???

2. You can't get an appropriate reading while the engine is running to determine back pressure. The pressure will fluctuate due to heat and fuel delivery. I'm only quoting the FSM.

Well you are reading the FSM incorrectly or the FSM is wrong or "special". Lots of resources, videos and test gauges have been developed to have the test done at IDLE and at 2500 rpm. Maybe a picture will help get this into your head?

The words inside one red band says "Idle" inside the other red band is "2500 rpm" because that is how the test is done. I am NOT saying performing the test while cranking the engine is wrong; you and the FSM can do and say whatever you like.

Sorry to OP for dragging this and other stuff out. Some of this might help a little, -while other stuff is mucking-up your thread. I am mostly replying to correct some of the mis-information or to learn myself.

 

[burlingamekay]

Got a code p0320

 

[Marde]

Cool. Code helps you find the problem.
P0320 - Ignition Engine Speed Input Circuit Malfunction

Trouble Code P0320
http://www.focusfanatics.com/forum/showthread.php?t=294155

That's why it seems to be working now. I replaced the coil, plugs and wires. The coil was badly cracked and I know the focus is knowen for bad coils. I will check the connector too. Thanks for the info annd I will keep you guys informed if I find anything wrong.

Also...
http://www.focusfanatics.com/forum/showthread.php?t=198464

And...
generally its a arching in the ignition system, coil issue or a plug issue
Read more: http://www.justanswer.com/ford/3rnhk-2003-ford-focus-code-p0320-possible-cause.html#ixzz3NWdRT9GV

And...
http://www.carobdcode.com/trouble-c...-speed-input-circuit-malfunction#.VKSXLivF9HU
Ford P0320 DTC Description:
Ignition failure sensor is used to check whether the spark ignition is occurred correctly or not and also used to tachometer drive. The sensor monitors the voltage difference between a resistance which is on the battery circuit for ignition coil. When the ignition coil works properly, the electric current through the resistance is detected as voltage drop. This is confirmed for every ignition event with the crankshaft sensor and the camshaft sensor. If Engine Control Module (ECM) detects a malfunction, no ignition is possible, so the engine would not start. If there is no ignition signal for a predetermined cycle for one or two ignition coils, an ignition coil circuit failure exists.