2000HF idle issues

[AussieLancia2000HF]

When my car starts from cold it will rev to around 2000 RPM and then drop back to around 800 to 900rpm after about 4 minutes
This seems to be its normal start procedure and has been for years
It is not a problem (or maybe it is?) but worth noting

When the car is warming up it will often struggle and will behave in quite a jerky manner as if it is a bit fuel starved. It generally overcomes this after 3 or 4 kilometre of travel but is always twitchy until fully warm

Once it is fully warmed up, and particularly on hot days, the revs will often cycle from 600 to around 800 rpm when at idle
If it is really hot (say 30 degrees Celsius plus daytime temperature) it starts to drop to around 600rpm
At that point it is prone to stalling
Once it does stall under these conditions it is very hard to get it started again.
I find I can crank the starter vigorously for sometimes a minute and it might start. If it doesn't, you push the car off the road and wait 5 or 10 minutes and it will generally get going again. If not wait a bit longer and so forth

As a result the car is unsafe to drive on hot days and you are always wary that it might stop at some inappropriate time in heavy traffic

They are the symptoms. The solution I don't know!

In recent times the injectors have been cleaned and the air slide has been replaced
I am not a mechanic but I do have one locally who is very good, but we are both a little stumped by this behaviour
Does this sound familiar ?

The car lives in Melbourne Australia and 30 degree Celcius days and hotter are common through summer
I'd appreciate any advice members might have on this issue

[LCV]

Hi,

I used to drive my 2000 ie Berlina (saloon) almost every day over 12 years. In the region where I live (south-west Germany) nearly 40° C in summer are not unusual, the winter is not very cold. Independent of the weather the car started always spontaneousely, about 1 minute with a little bit more than 1000/min and than running always with 950/min. I never had any problem. When I sold the car there were 430.000 kms on the clock.

I don't know if there are BOSCH dealers in Australia. Your car should have a BOSCH D-jetronic which was used in many different cars with 4, 6 or 8 cylinders. Unfortunately it is very difficult to find spareparts for the Lancia version because they did not sell many cars of this type and for BOSCH it is not interesting to start a re-production.

Do you have connections to the Brisbane area? I know, about 1600 kms from you, but I could give you a contact at the Gold Coast where they maybe can help you. Did you already ask the Australian Lancia Club?

Best regards
Frank

[AussieLancia2000HF]

Frank

Thanks for these suggestions. I have asked around in Australia and also the Flavia Consortium in the UK. So far the suggestions (which we are now trying) are:

The high rpm when starting from cold may be a clue here. It implies an air leak to me. It wouldn't have to be much of a leak, but it seems as though it closes up maybe as the engine warms, so the tick-over becomes more reasonable. 600/700 rpm is a bit slow here in experience, though a good tight engine will manage this. Normally (in the UK at least) an injection engine would need some hand throttle to lift the engine speed on a cold start, unless it's a warm day - or say a normal daytime temperature down under.

Have you pulled a spark plug at all? To see if the engine is running lean? A lean mixture can make for both erratic acceleration and hard restarting when hot. Another clue (for a lean mixture) might be a splashy misfire at tick-over.

There are quite a few places to check, assuming this is the cause. Manifold to head joints, anything that screws into the manifold, those round "O" ring thingys that the injectors mount with, the supplementary air thermostat pipes. This supplementary air stat can certainly misbehave, but you can pinch the pipe to eliminate that. Sometimes a good listen, when it's quiet and the engine has settled down, will give a clue when you can hear a hissing from somewhere.

Do check the fuel pump pressure plus the integrity of the pipework and filters. Low or varying fuel delivery could be another reason for all this annoyance.

Add to the check list fuel pump earth, Fuel Filters both of them... near pump and on inner wing. Are fuel rail pipes clear with no constrictions or kinks reducing flow. Remove all fuel and replace with new. When car will not start.. have you tried removing one injector to see if it is passing fuel? I have not had this on HF but on Alfa many years ago capacitor on sjde of Distributor went haywire when warmed up.

This is quite a list and I will report back as we progress (hopefully successfully!)

Rob

[LCV]

Will send you a pm.

[2000HF]

I have a Saab 99 E with D-Jetronic injection (my 2000 HF is still under construction). Since I checked the whole injection system the car is very reliable, but it took quite a bit to get there.

To check the D-Jetronic it is very very good if you have the original Bosch instructions for your model. You can find it on the CD with repair manuals for Flavia/2000. It gives information on trouble shooting and is a good guide for checking the system.

For the checking you would need a fuel pressure gauge and an ohm-meter. The special Bosch checking equipment is handy but not necessarily needed.
Before checking the injection of course you have to make sure everything else on the engine is in good condition – ignition, compression, valve clearance etc.

To me it also sounds like your engine is running too rich. Have you checked the fuel consumption? What do the spark plugs look like? By the way, the spark plugs can also cause temperature related problems. If engine, injection and ignition are okay and the problem still there you could try to use spark plugs with a higher thermal value than the ones recommended.

For the D-Jetronic:
First of all you will have to check the fuel pressure while running. Check if the the return line is blocked by pinching the rubber tube just behind the pressure valve. If the pressure in the fuel lines is rising, the return line should be okay, if not check for the blockage.
Adjust the fuel pressure at the pressure valve if necessary. When the engine is stopped the pressure should not suddenly drop. If it does the non-return valve in the (original?) fuel pump does not work. Build a separate non-return valve into the pressure side of fuel system close to the fuel pump. If fuel pressure drops slowly, then maybe the injectors are leaking.

Check the throttle clearance and the throttle switch and adjust if necessary. Check for wear on inside of throttle housing.

Adjust the idle with the idle screw (not with the screw for the throttle clearance!) ideally with a CO-Tester. If the revs are correct but the CO not right, this can be adjusted with the rotary knob on the ECU. By the way, with that knob I think you can also play around when the engine won´t start. But I think a well maintained D-Jetronic will always start

It is also good to check all sensors and the injectors for the right resistance. Also check if your car is actually equipped with the right parts – the part numbers you can find in the Bosch manual.

Original fuel pumps are very hard to source, but they can be replaced with modern types. Just make sure that it provides similar volume of petrol per time and a pressure of 2.5 to 3.0 Bar. The original fuel pumps have three connections, intake, pressure and overflow. Using a fuel pump with two connections the overflow line going to the fuel tank has to be closed and a separate non-return valve has to be installed.

I hope this all makes sense to you, I am not sure if I am using the right english technichical terms.

Best regards, Andre