Diagnostic code 14 (4) Timing Control System Malfunction - the investigation begins

[sim303]

Hi all

Some background first on a fault I am now investigating. Maybe it'll help someone some day:

My 1HD-FTE started acting up during a touring holiday a couple of weeks back. The first signs were when parking up one evening and the engine sounded intermintently rough whilst idling and manouvouring. Having done an oil flush and change just before leaving a few days previously, I checked the oil level and discovered it was above the max fill line. I can't categorically connect the two events, but I can say that in 8 years and 20k miles the motor has never faltered or glitched once, so this was concerning. At the campsite I drained approx 0.5-1 litre of oil, with a view to repeating later once remeasured. The problem recurred occasionally but did not significantly interfere with driving. In total, over the course of a few days I removed an estimated total of around 2 litres, to the point where the oil level appeared to be mid-level.

Despite this, over the last days of the trip, on the long drive from north Denmark to the UK, the problem became more severe, to the point of rough starting from cold, and on the last leg from the ferry having to resort to holding high revs (2k) in N when stopped in traffic etc, engine warning light coming on with drastic loss of power, then clearing somewhat, etc. The engine was sounding rougher overall and on occasions extremely so. I would say that had I needed another day to get back I may not have made it.

So, now the investigation starts!

1) I confirmed that the oil level is now OK. Maybe that was a red herring all along, but it does seem fishy....

2) Techstream reports DTC code 14 (4) - Timing Control System Malfunction

3) The FSM DI-14 advises this can be:

a - Open or short in Timing Control Valve circuit
b - Fuel Filter clogged
c - Fuel Freezing; Air In
d - Injector Pump internal pressure and TCV
e - Engine ECU

Regarding (b) - the Fuel Filter is 15 months / 5700 miles old, so that doesn't seem an obvious candidate. I have however ordered a replacement in case. I also have some injector cleaner, for what it's worth, although I haven't tried that yet.

Regarding (d), as per FSM FU-113 (Injection pump inspection) I have confirmed good resistance of the Spill Valve, TCV and Engine Speed sensor, and have confirmed a "click" from the TCV when energised directly. I took the chance to use some contact cleaner on the plugs of each sensor.

I've not yet ingestigated the other points, but I'm wondering if the Air intake could have become fouled, esp if the oil overfill was an issue.

Mileage is 187,300 mi.

Very interested to hear any thoughts. I'm planning to work through the remaining checks over the next week or so...

Will update when I have more

/sim303
Oh.... one other curve-ball.... more of a funny really... during the last oil fill, a bloody wasp got attracted to the oil flowing out of the bottle and before I could stop it had ridden the wave into the engine! I did immediately drain and filter the fresh oil to try to extract it but predictably I never saw it again.... That wasp may have been a messenger of doom...

 

[Dave]

I would start at the filter. First its easy to do, and you’ve done low mileage. Diesel is full of bio shit that grows well when not used much. Theres plenty of crappy filters out there also. Was it OEM? Do you add biocide to the fuel?

 

[sim303]

Oh, that is an interesting angle. I never knew that diesel bug were a thing, until now. I've seen that happen in screenwash and it's pretty nasty. My filter is a Crossland from ECP. No biocide. The fuel tank is near empty at the moment so I might just drain it completely as well as check / replace the filter. Thanks for the tip!

 

[Dave]

Crosland filters, were once a good quality, well known brand, especially amongst commercial users. But the brand was bought by ECP, so who knows what the quality is like nowadays, but its probably like all the other previous quality brand names that have been bought out and then used on crap products. Get a genuine one and start there. Theres also a sock in the fuel tank thats worth inspection.

 

[sim303]

Thanks @Dave

I replaced the fuel filter (for another Crossland I'm afraid as I'd already bought it a couple of days ago!). To avoid any chance of the new filter getting clogged if there were something unsavoury in the tank I also drained the tank completely. Nothing untoward came out. I put new diesel in (and injection cleaner) and went for a test drive, about 15 miles. During that time the problem did not seem to recurr, although it was previously somewhat intermittent in any case. Despite the promising signs I couldn't quite convince myself that the engine was a smooth as it used to be.

I tried another drive this evening and again it seemed "ok", but when I was parking up the lumpiness and occasional knocks returned

I plugged in the Techstream for live data. For what it's worth, when the "glitches" occur, the timing value changes quite drastically from around 15deg to 30-40deg (idling). So far no new error code have been raised (and the Engine Warning light has not been triggered).

So unfortuntately my relief at the apparent win was short lived and the quest resumes...

 

[sim303]

An update - (belated!) - on the above issue for interest. (Unfortunately I couldn't do much over the winter months, but I'm back on it now)...

After the last report, the CEL finally returned - as well as the bad running. I also notice that actual diesel (or some non aqueous liquid) was dripping out of the exhaust pipe on to my driveway at idle! As per the DTC 14 code, having ruled out the easy options, I tested the ECU as per the manual (various voltages, plus the oscilliscope tests). All seemed fine. I also opened it up to check for any water ingress (a couple of years ago my BMW would not run, due to what turned out to be water ingress in the ECU). The insides of the Cruiser one were spotless. I contact cleaned the pins & connectors and ruled the ECU out of the equation.

Given the unburned diesel coming out the back, I pulled the injectors and tested them on a cheap Chinese pop tester. Most if not all were opening at too low a pressure, and some were weeping (dripping) under a fraction of their pop pressure. Seemed like a good candidate for the exhaust drips, so I sent them off for recalibration / refurb.

In the meantime I took the chance to do the tappets and to clean out a metric tonne of oily soot from the intake tract - very messy and unpleasant.

Once the injectors came back I put it all back together and fired it up...

...the dripping had stopped, and the exhaust was waaaaay cleaner, but a test drive revealed that the timing issue and DTC 14 were not solved. I suppose I should not have been surprised as the injectors etc are not identified in the manual as a potential cause.

So whilst my injectors absolutely needed doing, they did not solve the problem.

After taking stock, the only suspect remaining on the list was the Injector Pump, even though the in-situ measurements appeared to be ok.

After a lot of research and hunting around, I was able to source a new Denso Timing Control Valve for the Denso ECD V4 injector pump used in the IHD-FTE (Toyota do not offer individual pump parts). Swapping it over was easier than expected.

Since then, no error codes have returned, and the poor and erratic running has stopped!

However... and this is where things now get murkey.. I still don't think the engine sounds quite right. The problem is, this is only based on memory and paranoia! It drives ok, but it just sounds a little ... agricultural. I know it's an old diesel, but my memory is that it was smoother than this. I feel like there is a noticeable (but not terrible) knock at idle. I also notice more of a shake when shutting off the engine, but again that could be my memory playing tricks. So I am at something of a loss. My biggest concern is that the period of bad runnin and bad timing caused permanent damage to BEBs etc

My other theory is that changing the TCV without getting the injector pump recalibrated may be sub-par. Whist I don't like throwing money at things, I am now at the point where if I knew the pump needed servicing, I would just go ahead and do it. But I'm somewhat reluctant to throw £1K + on a guess!