Yes I have taken it to a garage but he said tracing intermittent faults could cost a fortune so I thought I would try the STW wisdom.
Basically on some days it feels like an old fashioned petrol engine with a blocked jet or dirty plugs, hesitating, coughing and spluttering. Full throttle just produces a massive hesitation. Acceleration has to be done with very gentle pressure. The next day it behaves completely normally with no trace of yesterday’s problems. It doesn’t seem to make any difference whether tank is full or empty or outside temperature.
It is driving me mad so before I hand over my life savings what could be the problem?

Keep a log of when it rains and when this happens…?

No correlation so far between rain and problem.

I had an Astra which produced similar symptoms, sounds like the cars entering limp mode because its detected something isn’t right.

Could be EGR vale, Mass air flow meter, leaking boost pipe, faulty injector, ECU fault etc etc etc…

Try doing to “pedal test” and see which error codes show up (though these can sometimes be erroneous if a further problem has caused knock-on effects in other components)

1 Place one foot on the accelerator and one on the brake simultaneously
2 Insert the key into the ignition and turn to the second position (The dashboard lights will turn on but do not start the car)
3 Look at the mileage display and it will display any error codes that are saved in the ECU currently

Dunno then. Sounds like poor injector wiring or something. But.. if mild acceleration works then maybe that’s not it.

Could be something turbo related? Sticking vanes..?

I wouldn’t have thought it was limp mode, since when a fault is raised it’ll go into that mode and stay there. Engine won’t rev over a certain speed – and you’ll certainly get some kind of warning about it.

since when a fault is raised it’ll go into that mode and stay there.

This isn’t what my Astra did. It would sometimes enter limp mode, mid-journey, then behave normally 30 minutes later. Sometimes it stayed in limp mode for a week. Sometimes it worked fine for a week.

Sometimes a picture of a spanner appeared.
Sometimes it was a picture of an engine.
Sometimes no light at all.

Sometimes it limited the revs to 2500rpm, sometimes it was 1800rpm, sometimes no limit at all.

As you can probably guess, I had a particularly problematic one, but they don’t necessarily operate as logically as you’d expect.

What’s the mileage?
Is it regularly serviced?
Does this happen from cold, or only after the engine has warmed up?
How does it behave when idling?

This is the isuzu 1.7 diesel engine shared with the civic and astra etc…

It’s a common problem and is well documented including how to fix…. I can’t remember the cause off the top of my head ….Do a bit of googling about civics with the same engine and I think you will come across the issue.

Hope that is of some help.

Edit try

http://www.civinfo.com/forum/engines-transmission/42658-civic-cdti-s-2002-turbo-sensor-isues.html

Start with the basics and change the fuel and air filter if not done recently. Clean the MAF.

If still not working then look for split turbo pipes but that along with EGR normally results in excess smoke which you haven’t mentioned.

It’s an 06 Meriva, done 85000 miles, regularly serviced, idles fine and seems to kick in once warm.
It is very primitive in the instrument dept. and doesn’t have any digital readout type thingys.
I looked at the civic link and the symptoms sound familiar. You can however get above 50mph by very gently pressing the throttle down. As soon as you lose speed , from a gradient etc. , the symptoms return

That thread reads like my problems with the mechanic I had my Passat trouble with. Useless and expects me to shell out for his guesswork.

Still sounds like fuel starvation. Unless you’ve serviced it yourself and used quality filters get the fuel filter changed.

I had a similar problem, albeit with a different engine. The problem rapidly got worse in my case, and the vehicle became undriveable. It turned out to be ‘leaking’ injector washers. I think they’d started to break down, and let air in. They were only pennies to replace (plus labour).

Well worth having the egr valve off and giving it a good clean with carb cleaner. If symptoms persist, it is probably turbo related a la above forum link.

Just remembered, could also be the vacuum hoses. These control the operation of the turbo (i think). They are very thin silicone tubes, and if they split, can cause the turbo not to kick in, or operate intermittently.

You don’t need a fancy dash to read the fault codes btw, they appear on the mileometer.

Alternatively you can get cheap ODB2 fault code readers which plugin to the car and transmit fault codes via bluetooth or wifi to a smartphone.

Just remembered, could also be the vacuum hoses.

When I was younger I had a Pug 205 with a sunroof that, when closed, had a vacuum seal. The vacuum was generated by a pipe running from the manifold to the sunroof. When this pipe collapsed, the car stopped working.

Amazingly, my girlfriend’s dad somehow identified and fixed the problem in about 10 minutes (not a mechanic either).

johndoh – Member

Just remembered, could also be the vacuum hoses.

When I was younger I had a Pug 205 with a sunroof that, when closed, had a vacuum seal. The vacuum was generated by a pipe running from the manifold to the sunroof. When this pipe collapsed, the car stopped working.
You’re shitting me.

Could be the crank case sensor. If thats faulty you can get rough running and hesitancy on acceleration – almost like severe turbo lag little power below 2000 rpm and a surge above. On mine the sensor failed but didn’t give a fault light/ reading.

I replaced it with an after market one (if you are doing it / sourcing it yourself note there are two types of sensor depending on what brand of fuel pump the engine uses (bosch or something else I’ve forgotten) which works but the car doesn’t like. The car now runs fine but the EML is on telling me the crank sensor doesn’t work. Its a straight forward repair if you can get access – car needs to be on a ramp really. I just bought the sensor and asked the mechanic to bung it in when it was being serviced

Still sounds like fuel starvation

You can get a failed solder in the EDU (not the engine ECU on the top of the engine but another computer down the back, next to the fuel pump) that can cause fuel flow problems. – tends to be a bit more working / completely dead than rough running though. Its common for them to fail but a straightforward refurbishment – you should be able to remove the EDU yourself and post it off for exchange /repair for about £40.

It is very primitive in the instrument dept. and doesn’t have any digital readout type thingys.

no digital readout required for the pedal test – the code can be given by flashing the engine management light – one flash for 1, two flashes for 2 etc… ten flashes is zero. The codes are four digits long and you might have more than one fault code. They flash through the sequence pretty quickly – helps to have someone jot them down for you as you call them out. The pedal test downs’t work with all makes and models but its worth a try.