'98 Fiesta Ghia 1.25L 16v - Engine struggling to run

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Wed 8 Apr 2015 21:29
'98 Fiesta Ghia 1.25L 16v - Engine struggling to run - parkodrive

So, I have yet another issue with my troublesome Fiesta.

I was driving about town, engine operating fine for the 4 days before and up untill this came about, normal tempts etc, when I got a sudden loss of power and the car started jeking about. IVe checked all around and ive still got a full compliment of oil, and water/coolant. theres no smoke or steam and no smell of petrol. Theres no leaks or bits of metal anywhere so im certain I've not fragged it. theres still fuel to the rail even after 4 days and several starts.

This time it struggles to run. Basically, I start the engine, it starts fine but then it keeps dropping to around 250 rpm then back to normal idle then immediately back to 250 rpm. this is constant.

I have replaced the HT leads this afternoon and the issue still persists.

Ive pulled the leads and fired the engine one at a time starting with cylinder 1 (on the left). When the leads for 1 & 2 are pulled the engine fires up then almost imediately cuts out. When I pull the leads for cylinders 3 & 4, the engine continues to run, albeiot with the afformentioned issue.

The leads are definitely providing a voltage to all 4 cylinders. The only two causes I can think of are that its either a faulty coil pack (seemingly less likely as all 4 cylinders are recieving a spark) or blocked injectors on 3 & 4.

Has anyone had a similar issue?

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Thu 9 Apr 2015 14:31
'98 Fiesta Ghia 1.25L 16v - Engine struggling to run - Railroad.
Check the vacuum hoses underneath the inlet manifold. If they're split replace them. Also check the idle speed control valve to make sure it's clean and moves freely.

Does the engine otherwise run ok? If it lacks power a blocked or restricted exhaust could be the problem. If you have a vacuum gauge do some inlet manifold vacuum checks. This can give you a lot of useful information about the state of the engine.
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Thu 9 Apr 2015 15:00
'98 Fiesta Ghia 1.25L 16v - Engine struggling to run - parkodrive

The issue is that cylinders 3 and 4 are not firing. The engine struggles to run even at idle as its only running on 2 cylinders. So this rules out the idle valve (a problem ive had previously) as this gives an erractic idle, not an engine that struggles to run.

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Thu 9 Apr 2015 19:50
'98 Fiesta Ghia 1.25L 16v - Engine struggling to run - Railroad.
Have you done a cylinder compression check? A loss of compression on two adjacent cylinders is most likely a blown head gasket.

If the compression is good the next thing to check is the ignition coil, and ECM. The coil is actually two coils in one pack, and the plug has three pins. The centre pin is a common live supply. The outer two are the ECM returns, one for cylinders 1&4 and the other for cylinders 2&3. If your engine isn't firing on 3&4 then the ECU must be switching both coils. You could have the plug leads crossed over so check that one coil is firing 1&4 and the other 2&3.
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Thu 9 Apr 2015 21:17
'98 Fiesta Ghia 1.25L 16v - Engine struggling to run - parkodrive

Had another look at it this evening. Turns out it could actually be the clutch dragging. When I fire up the engine but hold the clutch in, the engine stutters then revs at 1400 and stays there for a couple of seconds before dropping to normal idle values. when i go to let the clutch out, the engine begins to stall, but fights it untill after a short while it cuts out.

Long story short: i think the cluctch is kaput.

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Thu 9 Apr 2015 22:04
'98 Fiesta Ghia 1.25L 16v - Engine struggling to run - Railroad.
What would that have to do with it only running on two cylinders?
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Mon 13 Apr 2015 20:56
'98 Fiesta Ghia 1.25L 16v - Engine struggling to run - parkodrive

After much poking about, I have replaced HT leads, coil pack and made sure of no leaks or other issues on this front. Turns out that it may actually be a clutch issue.

What I have now discovered is that when the engine is fired up, while holding the clutch in, the engine stutters then jumps to 1400rpm and holds there, firing on all 4 cylinders, running smoothly, with the revs dropping to 1000 after around 10-20 seconds, untill I let the clutch out. This is where things get annoying.

Now, when I let the clutch out, there is pressue as normal as you start to release it and the engine continues to run smooth untill you get the the point where you have almost completely engaged the clutch, then the engine drops to 250rpm then imediately cuts out.

I've asked about and one guy said that it could be the clutch cable snagging on something but I'm pretty certain this is not the issue as I belive my Fiesta uses a push rod set up which actuates hydraulics fed from the same resevoir as the brake system which leads me to believe that if there was an issue here, then it would also affect the brakes?

So the question is, if the clutch feels like its operating normally, what could be giving me the issue I've described above.

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Mon 13 Apr 2015 21:55
'98 Fiesta Ghia 1.25L 16v - Engine struggling to run - elekie&a/c doctor

Could be excess crankshaft end float.With the clutch out,the flywheel tdc sensor gap is increasing ,causing the engine ecu to misread the rpm information.Take out the tdc sensor to see if there are any impact marks on the nose of the sensor.

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Mon 13 Apr 2015 22:03
'98 Fiesta Ghia 1.25L 16v - Engine struggling to run - parkodrive

Where is this sensor located?

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