An old nemesis has returned !

[greyhulk]

Sadly this heck of an annoying problem of 'lumpy idle, misfiring & gradually cuts out' has returned.. It has happened twice on my driveway now with the car stationary & a few weeks ago it sounded like it backfired when i was out & about so i had to pull in very quickly! Struggled to start back up again but after leaving it a few minutes it did finally start & i was able to get home (thankfully)

So the car starts up first time with a lil bit of a rev but wont start with just a turn of the key (always been like this.) The revs do seem to keep rising once its started up, 1500rpm then fall down to idle at 1000, now it was around 1100rpm an 900rpm idle before so im not sure why it has suddenly increased.. (only thing that has been changed months ago was a severely cracked rubber hose from servo to plenum & the air filter to a k&n one, would this let more air in & possibly mess up the mixture? Please note it has been driven since & was totally fine untill past few weeks)

I cant actually get the car back to the auto electrician in Coventry who worked on it before, as it will most likely conk out at traffic lights/slow moving traffic & probably not start back up again leaving me stranded so im abit stumped.

Last year it had new ht leads, spark plugs, fuel pump, ignition coil has been checked over & is fine. Tony at Coventry car centre repaired the air flow meter which was a state inside (plate had dropped plus split on actual rubber cap) & it was running fine as i done a good 80mile in it there & back a few times.
Alan461 kindly came over & took a look last winter, he pointed out points on distributor cap were green, corroded, so i ended up replacing that for a new one.
Another point to make it is kept outside with a breathable cover on, would moisture possibly be getting at some electrical ignition parts? I know it was kept inside at auto electricians & didn't conk out once for him (typical eh)

Anyone got any ideas? Im not as mechanically minded as the rest of you on here so please bare with me

Steve

Edited by greyhulk on Wednesday 20th April 19:43

[greyhulk]

Top Gear TVR said:

If leaping to ideas if have gone for airflow meter or icv

Already had the airflow metre sorted out, the plate had dropped last time along with a split in the cap.. So I'm presuming that's all still working fine (I hope)

ICV hmm this was mentioned before actually, where can I locate it? Not sure what exactly I'm looking for

Cheers

[greyhulk]

RayTVR said:

If it's an S1 is this rhe 2.8 with the mechanical fuel injection?

Sorry yeah should of mentioned its the S1 2.8

[greyhulk]

Le TVR said:

Is it lumpy idle while warming up or just when hot?

When warming up, literally start the car up leave it running, then when it idles gets lumpy an eventually cuts out

[greyhulk]

mk1fan said:

It'll be that LED indicator relay.

Sorry, can't be any help on a 2.8.

that's been put on hold for now

Le TVR said:

I would start by looking for any possible air leaks on the intake side. Spray some EasyStart etc around the intake hoses and see if the engine reacts at all.
What do the plugs look like when it has cut out?

I replaced most of thecair intake rubber hoses with silicone few months ago, maybe ones worked loose? Or jubilee clip has possibly chafed one
Will take a look at the plugs when I get in from work, I did recall one looked a little white around the socket

[greyhulk]

Hi Loach1, I think the fact it dont start up witout some throttle is a issue i need to sort out, where can I locate the cold start injector is it the blue plug? (Sorry I'm useless with stuff like this)




I've just tightened up all the air intake hoses etc, used contact cleaner on a few electrical parts that were filthy.. Haven't checked inside the dizzy cap yet but as luck has it.. Its started up (with some throttle) & ticked over at around 13000rpm didn't seem to climb this time & idled at 1000-900rpm left it running for 15minutes, fan kicked in fine etc.. Hmm so all is well for now.. But i really want to sort this cold start injector thing out.

Edited by greyhulk on Thursday 21st April 18:11

[greyhulk]

Loach1 said:

Yes, it's the blue plug. Thanks for the pic too - it reminded me that there is an intake air by-pass valve too, which is the piece that is at the front of the plenum with the intake hose routed through it. When the engine is hot I believe the valve should be closed, letting the idle drop to the base setting on the throttle body. You could pinch that hose to simulate the valve in the 'warm' condition. It also has a coil in it that should close the valve as the engine warms up. It gets power from the green relay too, so you could check there to see if the green relay is supplying power to anything.

Come to think of it, if you have a voltmeter or test light, check to see if the cold start injector is getting any power when you crank. If not, check the air by-pass valve for power when running. If neither have power, it could be the green relay or the fuse associated with the green relay.

David

Cheers David, always find a pic easier sometimes , ive used some contact cleaner on the green relay it was covered in crap as was the cold start injector plug along with the black plug, red plug around the plenum.

I haven't got a voltmeter but ill have to pick one up, if the cold start injector wasn't getting any power at all would this stop the car starting up completely tho?

I did notice the PCV valve/hose doesn't look in great condition looks like its cracked abit, not sure whether this would interfere with anything?

[greyhulk]

Hmm this might be why it doesn't start without revs then, I'll listen out for the fuel pump next time I start it up.
As I say it is working fine now but for how long I don't know.. Still think something isn't making it run as smooth

Its gone dark here now but I'll take a snap tomorrow after work, did you mean the rubber air flow metre cap?

[greyhulk]

Will take a snap so you can have a look, pretty sure there's one there as Tony (Coventry car centre) who worked on my car set my mixture just right after it was messed up completely by other mechanic.

[greyhulk]

Loach1 said:

It's there! I forgot that the banjo fitting is horizontal for the control pressure.

So, as we were. I would check that there is power being supplied to the warm-up regulator and air bypass valve when running, and that there is voltage at the cold start injector when turning over.

I would also plug as many intake lines as possible (all but the brake servo) and see if things improve or the idle drops.

Thanks David, appreciated.
I'll try that out also ill try & source a replacement pcv valve elbow & just left of the 'cold start injector' theres a small split in the domed rubber cap.. These may or may not be effecting things

[greyhulk]

• Update

Past few days cars been starting up & idling fine, revs have been just right too.. Now today on the driveway it started fine but later on in the day i started it up & it was 1500rpm which seemed high again & when it idled it went lumpy & eventually cut out

Noticed a few rivets on the air filter box were loose, also the jubilee clip on the bottom of this hose was nowhere near tight it could be spun around.. Tightened it up & just taped the rivets for now, further testing required



reading the steve heath bible, im beginning to think the ignition module is failing, i remember 'greymrj' told me to replace this awhile ago as its probably the original one in the car, does anyone know what make/model ignition module i need for the S1 2.8?

Cheers

[greyhulk]

phillpot said:

Ford Capri 2.8 at a guess

cheers mike, i was told ages ago to replace both the ignition module & coil as there most likely the original ones on the car (greymrj's advice) so i thinkim finally going to do that.

Im pretty sure there is no air leaks from any of the intake hoses, the air flow meter was all sorted out by mechanic too & the car starts up first time (with gas) so im considering a new rotor arm & dizzy cap (bosch ones) may solve this occasional stalling when idling issue? It can only be something silly but i cant quite pinpoint what it is

If not i concede & will have to risk another trip to auto electricians if the car makes it on the motorway, theres nowhere local to me that i trust with an older car like this

Edited by greyhulk on Saturday 23 April 18:56

[greyhulk]

v8s4me said:

Is the part circled in red in good order, ie no cracks or splits? Faulty ones have featured on a couple of threads recently causing similar symptoms..

yeah I was one of those unlucky guys who had the split in the cap.. this is a replacement one checked it all over its fine, my next quest is trying to find the ICV & checking to see if its full of gunk or not

[greyhulk]

Loach1 said:

The 2.8 doesn't have an ICV as such. Idle is set at the throttle body when warmed up and for a higher idle when cold it uses the by-pass valve that is just below the green circle in your last picture (it has a blue hose on either side and an electrical connector for the heater cool inside). The key to a smooth running 2.8 is fuel pressure, so if you are satisfied that there are no intake leaks, that would be my next suggestion. Electrically it sounds find - you have a spark. That's all you need to run a 2.8.

To check fuel pressures (and correctly set mixture for all conditions), you need an old school mechanic that has a gauge set for Fords or VWs of the 80's. They must check line pressure and hot and cold control pressure and make adjustments as necessary to bring them back to normal. It's an expensive job because it takes time, especially the adjustment at the warm-up regulator. I think it was designed to be permanently set, but I bet a lot of cars have the wrong replacement warm up regulators installed, so they must be adjusted for the engine. They will owe you the corrected pressure numbers at the end of the job, so you know it was done correctly.

Also, the idle mixture can be adjusted independently. You might try this yourself with a very long 3mm Allen wrench. Make small adjustments and remember where it was if it doesn't improve. My guess is that you need to richen up a little, so give it 1/2 turn clockwise for starters.

Hi David, today its started up fine, idled at a steady 1000rpm no shaking either, sounded alot better too (did use some contact cleaner on the various plugs, electrical points etc, i think this car just likes to play games with me ) so im not going to tamper with the mixture for now

i still cant figure out why it wont start with just the turn of a key, possibly a failing ignition module, coil?
Ht leads & spark plugs are all new, along with dizzy cap (was a cheap intermotor one tho), may order a bosch one along with new rotor arm?

Edited by greyhulk on Sunday 24th April 12:45

[greyhulk]

Oh the one I had off other day, when you say open up, do you mean just separate it from the plug? If so I have already done that & used contact cleaner which got rid of loads of dirt & grit

[greyhulk]

phillpot said:

No, actually take the green cover off to expose all the innards.
Delicately clean and dry as required.

Oh I'll take another look if this damn weather drys up