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Hey guys,
I’m new to these parts of the Interwebs, and before getting to the topic at hand, I always feel the need to introduce myself, so I’m not a complete stranger!
My name’s Simon, I’m 18 years of age, and I am an absolute motorbike enthusiast, but cars interest me too.
I work as a software engineer (desktop, mobile, web) now. I started an apprenticeship as a motorbike mechanic; sadly I had to stop, due to permanent damage to my back. But I think I picked up quite a bit during that time, and feel comfortable working on cars and bikes alike.
I live in Germany, but I grew up in England, due to my dad serving in the British Army (42nd medical reg., I think?).
If you have any questions; I’m always up for them c:To the topic at hand.
After my motorcycle accident two weeks ago, my parents decided it was time for me to get a car, so I can at least get to work and school, and be independent of them (again).
A few weeks ago I became interested in a Ford Focus 1.4l (75bhp), took it for a drive and fell in love with the car. It does everything I need it to, it’s not exceptionally fast (being a 1.4l engine and all), but it gets me from A to B, and the previous owner souped the car up a bit, with a new exhaust system, an LPG system, 21″ rims, and put a new undercarriage on it (lowered the car down, and it’s pretty smooth driving).Today, my parents surprised me with the car, so we took it for a drive, we filled it up with both petrol and LPG, everything was fine.
My dad then wanted to use the car to get to work, and I agreed.
He came back a few minutes later, almost crying about how he “broke” my new car, and that the check engine light had come on. I then went to the car and took it for a drive. I noticed that the car was misbehaving (rough idle, power surging when accelerating, and the car just didn’t sound right). After driving a while longer, the check engine light began to flash, notifying me about a misfire on one or more of the cylinders. I quickly turned off the gas system, and the engine went back to normal. It was absolutely perfect. Just like I had remembered it. Pretty loud, backfiring when downshifting, and the engine smoothed out.I have no idea about gas systems, so I thought I’d better ask here, where there are a couple of mechanics, and other people who know their stuff better than I do.
What could cause this rough engine, when switching to gas, and how do I go about diagnosing this correctly?
It’s a Tartarini system, if I hadn’t mentioned before.Personally, I have a few culprits:
a) one or more of the injectors are buggered up
b) my ignition system is broken somewhere (if this is the case, probably coil packs or spark plugs)
c) the gas system is putting too much gas in the cylindersTomorrow when it’s daylight again, I am going to check the coil packs and spark plugs for any damage, and was going to do a load balance test (I think that’s what it’s called?) to see what I can find there.
Thanks in advance for helpful answers, and sorry for the long post!
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Welcome Simon! I’m Leo, I will try to impart some useful information here.
I will try to keep my answers simple since I don’t have a great deal of experience with lpg. I’ve watched a few videos about converting a car to lpg. Thereare many components as well as computer calibrations involved.
My first instinct is another calibration may be in order at a shop that handles lpg issues. I’m unsure of what precise performance parts were installed to the engine.
Some of the issues you mentioned seem a bit unrelated, but a few, such as backfiring sound like predetination. That happens when the spark ignites too soon before the piston is at top dead center. With the lpg system, the variables are bound to be different.
I could go on about other potential problems, but since you mentioned it runs fine on standard petrol then it would not amount to much.
Please keep us updated and again, welcome to the forum!
First of all buy a set of another wheels. I have 17inch rims on my 1.6 focus and trust me I want to change them, but now I can’t even change a spark plug at the car. 😛
I think, the most likely scenario, is that one of your LPG injectors, isn’t spraying any LPG, and that’s why you have that missfire issue, or it could be that the injectors aren’t synchronized in when they should spray and they give you that effect.
[quote=”peshewa” post=152833]Welcome Simon! I’m Leo, I will try to impart some useful information here.
I will try to keep my answers simple since I don’t have a great deal of experience with lpg. I’ve watched a few videos about converting a car to lpg. Thereare many components as well as computer calibrations involved.
My first instinct is another calibration may be in order at a shop that handles lpg issues. I’m unsure of what precise performance parts were installed to the engine.
Some of the issues you mentioned seem a bit unrelated, but a few, such as backfiring sound like predetination. That happens when the spark ignites too soon before the piston is at top dead center. With the lpg system, the variables are bound to be different.
I could go on about other potential problems, but since you mentioned it runs fine on standard petrol then it would not amount to much.
Please keep us updated and again, welcome to the forum![/quote]
Thanks for the warm welcome!
Sorry for not answering any earlier, I wanted to do some more observing before posting anything.
I checked the spark plugs and coil packs – they’re all brand new!
So I’m guessing it’s one or more of the injectors that’s defect, or as you mentioned a calibration issue.
I spoke to the dealer (well, can’t really call him a dealer, but it’s his business, dealing with cars, so hey), and he said that the car had been to the garage to get the gas system sorted out, some parts were replaced and repaired, because it was leaking and otherwise wouldn’t have gone through the German Tüv, and thus wouldn’t have been road-legal.
The car still has six months warranty, so he said he’ll get it all sorted – less work for me, I guess.[quote=”Gkikas” post=152854]
First of all buy a set of another wheels. I have 17inch rims on my 1.6 focus and trust me I want to change them, but now I can’t even change a spark plug at the car. 😛I think, the most likely scenario, is that one of your LPG injectors, isn’t spraying any LPG, and that’s why you have that missfire issue, or it could be that the injectors aren’t synchronized in when they should spray and they give you that effect.
[/quote]Nah, the tyre size is just fine 😉
I’m a pretty tall guy, so I can get to the different parts of the engine just fine.
I’ll be buying some big-ass jackstands next year so I can do some stuff under the car, too. It shouldn’t be a problem c:I was also thinking maybe one of the injectors isn’t spraying any LPG in to the engine, but I haven’t checked that yet. I wanted to do a power balance test, but I haven’t gotten to performing one yet.
I might do one tomorrow, though.I’ll let you guys know when I know more!
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