Variable Camshaft Timing

[jorton]

Operation

The oil control solenoid is part of the Variable Camshaft Timing (VCT) unit. The VCT unit used on the 2.0L DOHC engine is connected to the exhaust camshaft, and the rotation of the exhaust camshaft takes place in the VCT unit. The unit is oil filled to move the pistons inside the unit. Oil and piston movement inside the unit can retard the exhaust camshaft without affecting the intake camshaft. Adjustment of the VCT unit permits every piston position between maximum advance and maximum retardation.

Just wondering, should I follow any special routine maintenance practice since my car's engine has vct?

 

[Kestas]

This design is sensitive to deposits, sludged oil, or overly thick oil. If any of these conditions exist, the engine will run horribly and throw an error code for camshaft position sensor. Many have needlessly replaced the VCT solenoid because of this condition.

My personal experience was when I ran 20W-50 in the summer. It tripped the camshaft position sensor code and the engine died a few times. Swapping out the oil with 5W-30 solved the problem. This was five years ago. I still have the car. That engine does not like thick oil.

Just follow good oil maintenance practices. I have 195K on mine and use only regular oil and 3K oil changes. Perhaps your engine could benefit from an Auto-RX treatment as a preventive measure.

 

[Rustyknife]

if were talking ford, it uses a special oil filter fl 2005 with the wierdest looking [censored] metal valve in the end of it, they claim it wont start in the cold without it but I've used the fl 400s with no problems...so who knows

 

[mechtech2]

I also guess a Ford Zetec in a ZX2.
You can't run heavy oil in those cars. Lifter buckets stick when cold and they can run rough. Also, the VCT valve does not like thick oil or dirt.
So 5-20 or 5-30 will be good .
The FL2005 is double valved, but one is apparently for spillage protection when changing it.
The replacement is the FL400S.
It only has one antidrainback valve, but works just fine. The FL2005s are getting hard to find, and I think they are being phased out.

There is nothing you can do otherwise about your VCT. When installing a new timing belt and setting the timing, you have to rotate the cam forward against it's internal stop.

It is odd to have a variable exhaust cam. It acts like an EGR system, but also has the benefit of a longer power stroke, and we can eke out a bit more gas mileage in certain conditions.

That said, I would much rather have the variable system on the intake!

 

[TambourineMan]

We have a 1998 Ford ZX2 with 102,000 miles that has been throwing DTC codes P1380 and P1381 off and on (mostly on) for several years. It has the Zetec engine. It runs great. No stalling or roughness. Unfortunately this time it did not pass inspection. A Ford dealer replaced the wiring to the solenoid and that lasted for 5 miles. Now they say it needs a new timing belt and solenoid for over $1,100 which is way more than we want to spend. We might spend $500 to replace the timing belt and flush the VCT solenoid. We don't know what weight oil is in it now. I suspect 10w-30 as that is what most garages use. We are thinking of putting a light weight oil in it (0W-20?) and run it for a bit and see if the CEL stays off. I don't know if it has the proper filter or not, but we would put the correct one on it. If, as hinted above the VCT solenoid does not need to be replaced and the problem is just clogged holes through which the solenoid needs to get engine oil to actuate and we put a synthetic oil and also possibly something like Marvel Mystery Oil, do we risk loosening up a whole bunch of crud and making it worse?

 

[Kestas]

Lean on mechtech2 for advice on ZX2s. He probably knows more about these engines than Ford does.

 

[bdcardinal]

the FL-2005 is obsolete. cant even order some anymore. some dealers have some in stock still.

 

[punisher]

95% of the problems on the VCT of those engines is the actual VCT solenoid. Any time you get codes after the engine warms up that is the primary suspect. Mechanically the VCT mechanism is sound. Use the proper oil and use a filter with a proper drainback valve. Personally I never ran across cloggeg oil ports in the unit, but then again, we didn't get a lot of high mileage vehicles in the dealership. I broke more than one Torx bit getting the VCT unit out of those.

 

[RGrant]

VVT/VCT are very sensitive to oil weight. Only use manufacturer specified oil weight. Other than that, not really.

 

[TambourineMan]

If a dealer is (was) seeing only low mileage vehicles I am not surprised that they just went ahead and replaced the VCT solenoid whether it need to be replaced or not as it was probably covered by the extended emissions parts warranty and incurred no cost to them or the customer. I am hoping mine is OK. An earlier poster said many of these were replaced unnecessarily.

So I am still seeking opinions on my suggested method of using a very light weight synthetic oil with some sort of cleaning additive to see if it will clear up the holes (if that is in fact the problem) and it is not the timing belt or the solenoid itself. I guess to a certain extent if using a synthetic 0W-20 and Marvel Mystery oil makes it worse by loosening up long accumulated crud, that is OK since we will just junk it.

 

[mechtech2]

Tambourine - You may simply have a bad cam sensor. One bolt right in front and super easy to change. As you face the engine, it is on the right top, just below the valve cover.
This will cause other codes, ads the computer thinks the cam timing is off.
It's wiring, connector, or the sensor itself may be bad. A visual inspection and common sense may show you a problem.

It is taking a chance to throw parts at it without being sure, and this is not my style, but the sensor is cheap and is much less than having it checked at a shop. So it's your call.
Anyway, I'd start there.

Of course the VCT or cam timing system may be faulty, but check this first.

 

[SHOZ]

Originally Posted By: TambourineMan
We have a 1998 Ford ZX2 with 102,000 miles that has been throwing DTC codes P1380 and P1381 off and on (mostly on) for several years. It has the Zetec engine. It runs great. No stalling or roughness. Unfortunately this time it did not pass inspection. A Ford dealer replaced the wiring to the solenoid and that lasted for 5 miles. Now they say it needs a new timing belt and solenoid for over $1,100 which is way more than we want to spend. We might spend $500 to replace the timing belt and flush the VCT solenoid. We don't know what weight oil is in it now. I suspect 10w-30 as that is what most garages use. We are thinking of putting a light weight oil in it (0W-20?) and run it for a bit and see if the CEL stays off. I don't know if it has the proper filter or not, but we would put the correct one on it. If, as hinted above the VCT solenoid does not need to be replaced and the problem is just clogged holes through which the solenoid needs to get engine oil to actuate and we put a synthetic oil and also possibly something like Marvel Mystery Oil, do we risk loosening up a whole bunch of crud and making it worse?


DTC 1380 is an open or short in the VCT solenoid wiring or bad solenoid. You should be able to confirm this with an ohm meter.

Diagnostic Trouble Code (DTC) P1381 is stored when overadvanced cam timing is detected. DTC P1383 is stored when overretarded cam timing is detected. P1381 and P1383 are KOEO, KOER and Continuous Memory DTCs and will illuminate the Malfunction Indicator Lamp (MIL).

Possible causes for DTC P1381:

Cam Timing improperly set.
No oil flow to piston chamber.
Low oil pressure.
VCT solenoid valve stuck closed.
Camshaft advance mechanism binding (VCT unit).

 

[steve20]

0-20 & MMO = great plan
Let us know how it works out


Steve

 

[TambourineMan]

The cam sensor was replaced about 3 years and 10,000 miles ago sand that did not fix the problem at least for very long. Of course the sensor could have gone bad again. That simple fix went for $367 at a dealer. The wiring to the solenoid was fixed/replaced a month ago for $250 by the same dealer. that fix lasted 5miles and 5 minutes before the light came back on.

I don't believe it has ever thrown code 1383. It just throws 1380 and 1381. I don't think the CEL had been off much over the past four years, but as I said before, the engine runs great - it does not stall or hesitate and revs up normally.

So the question is now do we throw another $500 to do the timing belt and flush the solenoid holes, or $850 to do that plus a new solenoid, or give it up as a lost cause and spend $100 for a diagnosis at an official repair facility, hope that their repair estimate is more than $825, don't do any repairs and go for one time, one year non-renewable emissions extension?

I think I got my answer on whether I can switch to light weight synthetic oil and throw in some additive (MMO=Marvel Mystery Oil, correct?).

My question is whether the solenoid can be determined to be either working or defective without taking anything apart and spending a lot of money.

Here is a an extract on checking it which seems to imply that the solenoid can be checked by just tapping into various electrical posts and revving the engine, but if the oil or the timing is (also) a problem it would seem you also may not get the desired electrical readings and still not know fi the solenoid was good or bad:

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Code P1380 is strictly related to the electrical circuit of the solenoid, PCM and wiring. If the PCM tries to energize the VCT solenoid and doesn't see any current flow or too much current flow, Code P1380 will set. The normal resistance of the VCT solenoid is 3 to 6 ohms. That resistance should not change by any noticeable amount even with changes in temperature. If the resistance is OK at the PCM connector for the VCT solenoid (measuring from the vehicle power circuit, pin 71 or 97, to the control pin for the solenoid - usually pin 44 or 45), you can also perform an amp draw test on the circuit. With the PCM disconnected, turn the key on. Using a digital ammeter, place the negative lead of the meter on battery negative, and place the positive lead to the control pin for the VCT solenoid. The amp draw should be in the 2 to 4 amp range. Only leave the solenoid grounded long enough to get a reading, preferably no more than one or two seconds. The PCM normally duty cycles it, so leaving it fully grounded for more than a couple of seconds can cause damage to a solenoid that is still in working order.

Here's another test you can do to make sure it is mechanically working: With engine running, using a jumper wire, backprobe the ground side of the VCT solenoid. Then rev the engine up to 2,500 to 3,000 rpm and momentarily ground the VCT solenoid; again, only for one to two seconds. You should hear a noticeable difference in the way the engine runs.

This same test can be performed to help diagnose a Code P1381, which indicates that when the PCM commanded the VCT solenoid to operate and retard the cam timing, it did not see any or enough change. This can be caused by a mechanical problem with the cam gear assembly, a bad VCT solenoid, or a problem with contaminated engine oil. Since the VCT solenoid relies heavily on oil flow to create the force to move the cam gear assembly, anything that causes poor oil flow, such as dirty oil, metal chips or flakes in the oil, can affect how well the VCT solenoid functions.

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[punisher]

Once it throws the P1380, you know it is an electrical fault in the VCT solenoid/circuit, no real need to perform function tests. You can ignore other VCT codes as well. Once the MIL lights up (usually after the engine warms up), pop the VCT connector off the solenoid and ohm it. If it is in spec start on the harness checks.

 

[oilyriser]

Can this engine run without VCT?

 

[mechtech2]

It will run, but not well.
The exhaust cam can flop around.
There is a VCT delete kit which locks the timing like a normal car, but you will get an engine code light without a chip or flash.

But like I said, other problems have to be checked . Other things can cause a code. Like an O2 sensor code does not necessarily mean the O2 is bad, it could have a vacuum leak, bad MAF, regulator, etc..

 

[Rabbler]

Originally Posted By: mechtech2
It will run, but not well.
The exhaust cam can flop around.

That's interesting
Most of the VVT systems I'm familiar with will default to the neutral or full advance position.

Does this system's actuator not have a lock pin or spring to hold it in default?

 

[mechtech2]

Ford's Zetec with the variable Exhaust cam is a system unto it's own.
There is no lock. Even when setting cam timing, you have to rotate the E cam forward against it's stop.