Flashing engine light

[Lord Voltermore]

I dont know much about this,  but from what I have just read elsewhere   the most likely causes of a P0203 fault is a faulty injector , OR faulty wiring to the injector   OR a faulty PCM/ ECU not sending the correct signals.       With the most likely being the injector  , and only rarely the PCM .  The P0303 misfire is probably just a consequence of the P0203  fault.

There are various tests that can be made on the injector, including swopping them over to see if the fault migrates  to which ever cylinder now has that faulty injector.   And also measuring whatever signals,if any,  the injector is receiving from the ECU.
Maybe the proper  tests have been carried out but I am confused as to why although they have said the wiring is OK,  they cannot identify whether its the injector or the ECU that is faulty.  Can it really be both at the same time ?  Maybe its cheaper in parts and labour time just to change both for a sure fix rather than carry out tests.  Or is there something I've missed?

[obtom]

Thanks for all the replies so far. I'm really tempted to start with just getting a new injector and seeing what happens then.

In terms of why both the ECU and injector might both have failed I'd read that a faulty injector sometimes damages the ECU in the process due to bad ECU design? I think that Westy36 is right about the location of the ECU - it's the right size from what I see on the ecutesting images. I couldn't get the plastic cover off to have a look at the fastenings as I suspect the battery needs to come out first to get the cover off. But I've done that before so that's ok.

If I get another injector, any thoughts on whether to go with a cheap new one or genuine used one? And how best to get the right part?

I saw on the honda parts website this part:
https://hondadirectparts.co.uk/parts/honda-civic-genuine-parts/honda-civic-2012-2016-genuine-parts/engine-service-kits-honda-civic-2012/honda-jazz-2009-2015-injector/
Giving a part number of: 16450-RB0-003

But when I searched on ebay I quite often saw mentions of the mk3 Jazz rather than mk2? Would either of these parts be suitable:
https://www.ebay.co.uk/itm/134802488185 (new cheap part)
https://www.ebay.co.uk/itm/355547695592 (OEM secondhand)

Thanks again, really appreciate all the help

[Westy36]

Yeah it's confusing, but the mk2 is sometimes listed as a mk3 on ebay an the like. Mk2 we understand to be the 08-15, and the mk3 15-20.

£328.20 Inc VAT for a new Honda injector!  Wow, that seems so expensive to me.

Injector replacement requires removal of the intake manifold. If this is somthing you're happy to do, then have a swap about as suggested by our LordV has to be worth a go. 

With regard to the ebay listings, I would seriously consider the OEM item at £54. The other just looks to cheap?

Personally I would get the engine code for my car, and phone some breakers. Professional breakers will sell the part with warranty. They often just list Jazz as breaking on ebay such as eBay item number:186421190286- get in touch and see what the injectors would cost. You've got 4 to play with then. At least that's what I would probably do, cost effective and end up with used Honda parts. And if you're not paying for labour, this hopefully will not be too expensive to sort.

[obtom]

Thought I'd give a bit of an update in case it's of use for anyone else:

I ended up ordering an OEM injector from an eBay seller for about £55. It was sold as having possible cosmetic defects but looked perfect to my untrained eye so happy with that. The seller even provided a return envelope for the old one (which they confirmed to be defective after receiving it).

I wasn't confident in replacing the injector myself so took it to another local garage who did the job for me for £50. They said it was an awkward one to change (number 3) and it was there a couple of hours so I'm glad I didn't attempt that one. They reset the error code on the ECU but it kept coming back (engine warning light etc.).

So, I think, must be a damaged ECU. I take the car back home and remove the ECU myself to send off to ECUTesting for a rebuild. To remove the ECU (2014 Jazz), take out the battery (ECU is mounted vertically behind it), take the black plastic cover off and undo the 3 bolts. Then flip a little plastic lever on each of the wiring looms going into it and take the whole thing out. (None of this was easy for me as needless to say it had started raining, I didn't have the best tools for removing bolts and my fingernails are quite brittle so not great for flipping wiring levers). Anyway, managed it and sent ECU off for rebuild.

Great service from ECUTesting. They kept me informed of delivery and had a message to say that they'd hooked it up to their load tester and ... there was nothing wrong with it. Offered me the choice to rebuild it anyway (I think they update the components) or just send it back, minus the testing fee. I said they might as well rebuild it, which they did.

When I got it back, I put it back together and ... touch wood ... the car seems to work. Been using it for a couple of weeks in mixed conditions. Perhaps it's a bit sluggish but the spark plugs are due a change anyway so could be that. I've got no idea why it worked after an ECU rebuild when there was supposedly nothing wrong with it!

Lots of thanks to all you who helped me, particularly Westy36 and Lord Voltermore, and fingers crossed you've given me some more usage out of my little Jazz. Now just need to sort out the plugs, rear brakes, ....

Tom

[olduser1]

Good news the lesson being avoid garages who fix faults by clearing codes. That's not quite how to tackle fault codes.
Good luck with your "new" Jazz.

[Westy36]

Nice one Tom  Really pleased you got it sorted.

Sounds like removal of the ECU was a pain for you. FWIW, when I do a job on my cars, I sometimes treat myself to a tool. The £ I've saved in labour more than pays for it. Over the years, I've built up a a fairly decent tool kit. If I were you, I'd temtped to do likewise and invest in a few basics with the money you've saved to preserve your brittle nails if you need to tackle another job in the future.

The garage you used looked after you on the price. Maybe name them on a new thread as a recommendation in your area to help others? Just a thought.

Here's to many thousands of trouble free miles in the future!  Brilliant little cars the Jazz.

 

[embee]

One of the most common things causing electrical issues are connectors. I worked in the auto industry (design/development) including aspects of reliability and have studied loads of in-field fault reports.
ECUs are generally pretty reliable,  it might well be the simple action of unlatching and removing the ECU connectors then refitting them which "fixed" the problem.
The first thing I always do when faced with a tricky issue is unplug it and plug it back in. (A bit simplistic and tongue in cheek but you get the idea).

[Westy36]

Good advice Embee. Would you recommend a spray of any kind to help, such as electrical contact stuff?

[embee]

Depends a bit what the pins/sockets look like and where they are situated. Usually some aerosol contact cleaner won't do any harm. If there are signs of significant tarnish or even corrosion on the surfaces then any cleaning efforts will usually improve things. Anywhere well protected from the elements I wouldn't usually use any dielectric grease for example,  but if it's likely to be exposed to wet and looks vulnerable then definitely consider it.
You can get pin cleaning tweezers with abrasive tips which can be useful  (Sealey do some), though I find they are often a bit big for modern small pin connectors.

[GBH]

Totally agree with embee. Have had two cars (of german make) where unfathomable electrical problems were resolved by cleaning the connectors.

First was with a family owned car where it would randomly fail to start. (e.g. drive somewhere to drop someone off, turn ignition off and say "call me when you need picking up", turn ignition on and car was totally dead! Wait 10 minutes and try to start again and sometimes it would start and sometimes you had to wait and try again, and then sometimes again!) - Problem found to be corrosion on several main loom connectors.

Second case was where the car would take ages to get to full performance. Started and ran O.K. but would not accelerate properly until engine was fully warmed. Pulling out of a side road was a nightmare! Resolved by removing the ECU and cleaning all the connecting pins / sickets.