My new car! 1998 Ford Mondeo ST24 2.5 V6
Discussion
If you have had it working at all then the transistors are probably fine. Good thinking taking it to a TV repairers, they are used to looking for tricky dry joints and bad connections, and £20 sounds very reasonable. They will probably check anyway, but tell them to have a look at any electrolytic capacitors. They can lose their electrolyte as they dry out in the high under bonnet temperature.
Failing as it heat cycles is a classic symptom of a dry joint, but consider that it might also be an oxidised connector or dry joint in the loom plug itself.
It does make a heck of a difference doesn't it! I remember way back when we were looking for a V6 Mondeo for my dad, the first couple of cars we saw had failed valves and I felt a fraud for telling him how good the engines were because they felt so gutless. Then he drove a good one. The bad news is that it becomes so tempting to drive it with the secondaries open, which kinda kills the mpg.
Failing as it heat cycles is a classic symptom of a dry joint, but consider that it might also be an oxidised connector or dry joint in the loom plug itself.
It does make a heck of a difference doesn't it! I remember way back when we were looking for a V6 Mondeo for my dad, the first couple of cars we saw had failed valves and I felt a fraud for telling him how good the engines were because they felt so gutless. Then he drove a good one. The bad news is that it becomes so tempting to drive it with the secondaries open, which kinda kills the mpg.
As you may or may not know, this weekend was incredibly wet up here in Inverness and I (rather stupidly) drove through a massive puddle that was actually much deeper than it looked. Result? A very rattly heat shield. Ripped the bugger off and all is well 
Touch wood still running brilliantly after 1000 miles
Transistors have dispatched so should be here tomorrow with any luck, then it is going straight to the TV repair place. Can't wait to get it back to 100%, it feels a bit depressing when I drive it hard at the moment because I now know what it is capable of
Touch wood still running brilliantly after 1000 miles
Transistors have dispatched so should be here tomorrow with any luck, then it is going straight to the TV repair place. Can't wait to get it back to 100%, it feels a bit depressing when I drive it hard at the moment because I now know what it is capable of
Can I recommend this..
http://cgi.ebay.co.uk/st200-airbox-bellow-and-thro...
Had one on my ST24 and it was perfect! There is a part missing though, the actual air feed that is in the wing is a lot bigger on ST200's.
See my photos here when I got a few brand new from ford parts UK!
Mine also made 172bhp with the airbox fitted but not sure what they make usually anyway!
http://cgi.ebay.co.uk/st200-airbox-bellow-and-thro...
Had one on my ST24 and it was perfect! There is a part missing though, the actual air feed that is in the wing is a lot bigger on ST200's.
See my photos here when I got a few brand new from ford parts UK!
Mine also made 172bhp with the airbox fitted but not sure what they make usually anyway!
I bought a few old stock items for about £20-30 each I think, this was a couple of years ago though!
Try these guys, never know they may still have some. http://www.fordpartsuk.com/
If not, the parts seem to be available and cheap second hand..
http://completed.shop.ebay.co.uk/i.html?rt=nc&...
Try these guys, never know they may still have some. http://www.fordpartsuk.com/
If not, the parts seem to be available and cheap second hand..
http://completed.shop.ebay.co.uk/i.html?rt=nc&...
Edited by Max M4X WW on Monday 18th July 20:26
It may be the Mk.1 version of the engine, but I seem to remember that the secondary throttle butterflies sometimes refused to operate because they were gummed up. If new transistors and sweating up the joints doesn't work, then it might be worthwhile taking off the upper inlet manifold to see how clogged it is.
Update - got the circuit board back but the b
d thing still doesn't work 
The guy at the TV repair shop said the board is fine and everything is working, so I put it in but still no luck.
I tried revving the car from the engine and looking at the little cogs in the IMRC but they are not doing anything regardless of revs.
Any ideas?
d thing still doesn't work The guy at the TV repair shop said the board is fine and everything is working, so I put it in but still no luck.
I tried revving the car from the engine and looking at the little cogs in the IMRC but they are not doing anything regardless of revs.
Any ideas?
It is very difficult to do much more without some test equipment. The electronics bloke probably checked over the solder connections looking for "dry" joints. That is to say ones that have mechanically broken down. As someone else has mentioned, you need to check the unit is getting the right input data, and that the IMRC motors are getting the signal. I suspect one of the connectors in the circuit has oxidised and is intermittently open circuit, stopping either the input or output signals from getting through.
I was going to recommend the TalkFord.com forum, but I just checked and I see you are there already
I was going to recommend the TalkFord.com forum, but I just checked and I see you are there already
) so hopefully that will get a result. Podie said:
ST170 and Mk3 Mondeo are the same callipers. The setup gives you a 300mm front brake setup.
Depending on the calliper stamp on the ones on the ST24 they'll be desirable to TVR Griffith and Chimaera owners looking to upgrade.
This is a common misconception, the Mk3 Mondeo Caliper Pistons are much smaller than those in the ST170.Depending on the calliper stamp on the ones on the ST24 they'll be desirable to TVR Griffith and Chimaera owners looking to upgrade.
I can only say how I would approach it, but bear in mind that I am an electronics engineer.
First of all, with the aid of a wiring diagram (Haynes manual for example) and a multimeter or test lamp, make sure the unit is actually getting power when the engine is running. Whilst checking that, I would check the signals it is getting from the engine. Without a wiring diagram it is difficult to tell you what to expect. Possibly one wire that feeds to the throttle potentiometer and another to the engine management that activates at 3750rpm, but that would be a guess.
If you can, with the engine off, and unit removed, see if you can manually operate the inlet valves. If they are jammed or very stiff then they obviously need to be cleaned.
With the IMRC open, check that the motor is free and able to rotate.
Unsolder one of the motor wires, and check continuity with a meter. It should be low resistance. If it is high resistance (open circuit) then maybe try putting 12V across the terminals to see if it still runs.
I see from various photos that there is a crude switch on board which uses a cam to press a piece of copper against a contact. Make sure the contact is clean and opening / closing when it should. It might be that a bad contact is causing the unit thinks the valves are open anyway and is disabling the motor. Top of the PCB in this photo:
Looking here http://fordwiki.co.uk/index.php/Fix_IMRC it seems that IMRC loom wires may become damaged. It is worth checking their condition.
I know some people connect a 12V lamp across the motor feed (via a pair or long wires) which tells them when it is activating. This would at least tell you that the motor is getting power at the right time (or not). Just blipping the throttle wide open should activate it.
First of all, with the aid of a wiring diagram (Haynes manual for example) and a multimeter or test lamp, make sure the unit is actually getting power when the engine is running. Whilst checking that, I would check the signals it is getting from the engine. Without a wiring diagram it is difficult to tell you what to expect. Possibly one wire that feeds to the throttle potentiometer and another to the engine management that activates at 3750rpm, but that would be a guess.
If you can, with the engine off, and unit removed, see if you can manually operate the inlet valves. If they are jammed or very stiff then they obviously need to be cleaned.
With the IMRC open, check that the motor is free and able to rotate.
Unsolder one of the motor wires, and check continuity with a meter. It should be low resistance. If it is high resistance (open circuit) then maybe try putting 12V across the terminals to see if it still runs.
I see from various photos that there is a crude switch on board which uses a cam to press a piece of copper against a contact. Make sure the contact is clean and opening / closing when it should. It might be that a bad contact is causing the unit thinks the valves are open anyway and is disabling the motor. Top of the PCB in this photo:
Looking here http://fordwiki.co.uk/index.php/Fix_IMRC it seems that IMRC loom wires may become damaged. It is worth checking their condition.
I know some people connect a 12V lamp across the motor feed (via a pair or long wires) which tells them when it is activating. This would at least tell you that the motor is getting power at the right time (or not). Just blipping the throttle wide open should activate it.
Quick update - it decided that it wanted to work again on a drive over the west coast, car sat for a week, and on the way back today it decided it didn't want to work
This is good though, as it tells me that the circuit board is working fine and the intermittent problem lies elsewhere.
What would be the best course of action? I would imagine getting the IMRC wiring re done, and maybe cleaning out the secondaries? Would that be the way to go?
Also, my Dad reckons that a bit of WD-40 on the cogs under the bonnet might help, would that do anything?
This is good though, as it tells me that the circuit board is working fine and the intermittent problem lies elsewhere.
What would be the best course of action? I would imagine getting the IMRC wiring re done, and maybe cleaning out the secondaries? Would that be the way to go?
Also, my Dad reckons that a bit of WD-40 on the cogs under the bonnet might help, would that do anything?
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