Noisy injectors (UPDATE with video)

[myjalopy]

I assume you have checked the obvious, like binding brakes? especially the handbrake.

But it keeps coming back to the temp gauge, if the ECU thinks the engine is cold, it is going to use more fuel.

Yes, I checked the brakes first. The handbrake was adjusted too much, so i let it off a bit, but the brakes don't bind. I would change the sensor for the fiver it costs, but I am quite sure it's not that after testing it.

[myjalopy]

Well, generally you can't tell much from a plug chop if they've been in a while, 'cos then it's an average of what it's done over the course of the time. They don't look super-rich though. Or oily, thankfully. But you can't really tell that much if they're not of a known age. Nothing there to get too worried about, I'd think. I've seen 'em black from too much fuel on an over-rich mixture (awaits keyboard warriors saying this isn't possible!). But there has to be a reason why your car is giving such crappy gas mileage.

Plug chop? :wonder:

I think the sparks are OK, it starts first time each time. As far as black plugs go, yes I have seen them on an old Sierra I had.

Starting to get really p***ed off, especially when i read posts talking about getting 48mpg from a Felicia !

Now I read that you have to put a special antifreeze in Skodas, just after I topped mine up with normal stuff. Got to phone around the shops now and see who supplies this wonderful elixir !

I am thinking of going to look at a Polo today, 1.4. Older and much higher mileage, 123k, but probably much less hassle. :S

[djaychela]

i.e. put in a new plug, and run the car for say 10 minutes, and see what the plug looks like.

I've never got -great- mileage from my recce Felicia, even after putting in a new thermostat the main bonus was the heater warms up quickly. However, on a cruise, even the rally car will manage over 30mpg, and bear in mind that's got a C/R box in there where 5th gear is about the same gearing as 3rd-and-a-half on a standard box, so the engine is revving like crazy, and it will only do 98mph when it's flat out at 7200rpm.

One thing: Have you ever tried removing the fan belt and running the car (briefly, obviously, as the water pump will be disconnected, so only run it for a few seconds) to see if it's quieter like that?

[myjalopy]

One thing: Have you ever tried removing the fan belt and running the car (briefly, obviously, as the water pump will be disconnected, so only run it for a few seconds) to see if it's quieter like that?

No I haven't, but I will give anything a go. You think the pump could be making all that noise?

[TeflonTom]

Now I read that you have to put a special antifreeze in Skodas, just after I topped mine up with normal stuff.

i wont tell you about the power steering fluid you need to use then :wonder:

[djaychela]

No I haven't, but I will give anything a go. You think the pump could be making all that noise?

Worth checking, as it's a 2 minute job to do it. Had an Escort years ago that had a noisy alternator, and it was that draggy that it made a difference in the fuel consumption, and another OHV car which had a noisy water pump which wasn't easy to diagnose until I pulled the belt.

[myjalopy]

Yes, will do that.

I have just flushed and refilled the coolant now having topped up with the 'wrong' stuff and just running it up to temp.

Having a close listen to the engine as it warms up I am convinced the sound is coming from the back of the block. It is a tap, tap, tap which i think could be closely linked to the rhythm of the firing of one cylinder? I am going to try and get to the exhaust and see if there is any tell tell black soot anywhere. Not easy as it's very tight.

What do you reckon, is that I likely culprit or would that just not happen?

[djaychela]

An exhaust blow near to the exhaust valve (i.e. where the manifold joins the head) can sound like a mechanical fault. I once bought a GSXR750 from a guy who told me the engine was knackered, having been told by his local bike shop that the big ends had gone (I had a spare engine and planned to change it). Picked it up, and thought I'd run the engine anyway, just to see what was wrong, particularly as when I picked it up he told me he'd ridden it for 30 miles after the problem developed (which it would definitely not have survived). What had happened was the exhaust was held in place with split collets, and some idiot in the same bike shop had fitted them the wrong way round, and one cylinder's exhaust was leaking a bit. Putting them back in place liberated a perfectly-running bike.

Worth checking, and easily done, but the sound that I heard on the video didn't sound like that to me. But there's definitely something not right with yours...

[myjalopy]

Worth checking, and easily done, but the sound that I heard on the video didn't sound like that to me. But there's definitely something not right with yours...

Yes, but the sound on the video is misleading. The microphone picked up noises from all over and magnified them. I will try to do it again, maybe from slightly further away from the engine bay.

Maybe one day I could make my way down to Bournemouth so you could hear it. No, actually I don't think I could afford the fuel

Edited 12 March, 2010 by myjalopy

[djaychela]

Yeah, well if you want to and I'm about, it might save on internet bandwidth! :p

[myjalopy]

Gave the car a nice clean today, top to bottom, new air freshner as well. I'm sure that's all it needed and it will drive perfectly now :no:

Edited 12 March, 2010 by myjalopy

[myjalopy]

Engine still rattly, so got around to adjusting the tappets yesterday. They were too tight if anything, but not noticed any difference to be honest. At least it hasn't got any more rattly. Tried to tighten up the exhaust nuts that I could get to too, some needed a tiny bit doing up. Tap, tap still there though.

I'm happy to put up with it as long as I can better mpg, which I think is beyond this particular Felicia

Darren, I have not yet taken the belt off as I am quite sure the noise is not the water pump.