CA20E running RICH... wonder what's wrong.

[TurboZ.Dude]

Hello there C!

Thanks for the suggestion! That may be a go after we find out if the fpr truly is broken as we believe it is.

Adjustable FPRs with a gauge are expensive over here... about AUD 350 at the cheapest.

We can get a stock fpr from the junkyard for less than AUD 70. So that's the first thing we will try. But we will probably get an aftermarket one sooner or later, they are very useful and above all reliable.

[Callumgw]

Hello there C!

Thanks for the suggestion! That may be a go after we find out if the fpr truly is broken as we believe it is.

Adjustable FPRs with a gauge are expensive over here... about AUD 350 at the cheapest.

We can get a stock fpr from the junkyard for less than AUD 70. So that's the first thing we will try. But we will probably get an aftermarket one sooner or later, they are very useful and above all reliable.

really? we can get them for about AUD$60:
http://cgi.ebay.com.au/FUEL-PRESSURE-RE ... 286.c0.m14

maybe try ebay.....

C

[TurboZ.Dude]

What? Are you serious? That's very cheap! Good to know!

I'll try to look for some cheap regulators now, but we have very high taxes over here so I don't expect to see anything that cheap domestically. I may have to "import" one from Ebay. But I don't like auctions, they give me too much of an adrenaline kick.

[long explanation]
The reason to why I don't want to use an aftermarket fpr right away is that I don't want to fix an overfuelling problem by masking the cause. If the problem is actually caused by something else than the fpr, and we use an aftermarket fpr to "solve" the problem we may get the fuel pressure low enough for the engine to run well at low rpm but lean out at high rpm. In the process we may blow the engine.

Replacing the original fpr only confirms that it is or isn't broken. If the overfuelling continues after replacing it, we know we have to look for the cause of the problem elsewhere.
[/long explanation]

It is tempting to get an aftermarket fpr. After getting the engine running properly, if I find one with a suitable price tag, I'll buy it.

Cheers,
Jan

[Callumgw]

buy it now GBP22 +GBP4 from the UK...

http://cgi.ebay.co.uk/NEW-SUBARU-IMPREZ ... 286.c0.m14


C

[TurboZ.Dude]

Hey thanks! That's very affordable, now that it is that close to my location! :D

[TurboZ.Dude]

The fuel pressure regulator seems to have been broken. I replaced it with another stock one. Now the mixture is correct when the vacuum is OK, but the problem is; it's occasionally losing vacuum all the way down to zero and the engine coughs, runs on 3 cylinders, and at approx. 500 rpm. Giving it a bit of throttle doesn't help, but giving it a lot of throttle does... after a while the engine starts building up revs and starts to run on all 4 cylinders again. And the vacuum builds up, so the engine runs better again. But even when it's running a bit better, it's hunting a bit... not with a high frequency though. It's running at about 1000 rpm for about 30 seconds... then at some point it probably loses vacuum and the revs drop to below 500... after which the revs rise up to 1500, and after a few seconds it's down to 1000 again.

It's very hard for me to guess what's wrong now, but at least the engine isn't getting too much fuel anymore. It's like it's getting too little actually. The exhaust gases are clean and invisible now, except for when I give it a lot of throttle to "prevent" it from stopping. I know, this is not a professional approach. But face it; I'm an amateur!

And one more thing... the green led on the ecu doesn't light up as far as I've seen. Even though the running condition seems to be lean, judging by the exhaust gases. The green led should light up when lean condition is detected.

At least I'm making progress... it's running a lot better now than it was before changing the regulator! :D

[Callumgw]

I think most would agree "judging the exhaust gases" is not a good method of figuring if the vehicle is lean. Does sound like a vacuum leak, or possibly the idle up system having a bit of a failure.

Best thing it to go round and check each vacuum line and intake pipe connection. Make sure everything is actually connected and that nothing is split. Sometime good to remove and reconnect just to be sure.

C

[TurboZ.Dude]

Hehe yup I know. I'll check out all the hoses, replace them, and then I'll take a look at the idle up system... that may be a bit more difficult issue if it isn't working properly.

Thanks M8! I'm sure I'll get this engine running properly soon!

[TurboZ.Dude]

How stupid I've been. It's very simple: I've blocked off two coolant hose taps behind the throttle body. After a bit of research I found out that the idle up is not getting any coolant. And it looks like it gets its' coolant from the taps behind the t/b. So the only thing I've Gerry-rigged is the reason to all of the running problems.

I Gerry-rigged that because somebody at ZXOC told me those were vacuum lines. However, that must have been incorrect. Since when have thinner vacuum lines started to have hose clamps (these hoses do)? Somebody at ZXOC told me recently that they are coolant taps. So things started to add up... I hadn't given those hoses a second thought. So I've learned a lesson now.

[TurboZ.Dude]

It's alive! :mrgreen::mrgreen::mrgreen::mrgreen::mrgreen::mrgreen::mrgreen::mrgreen::mrgreen:

Thanks to you guys I've learned a bit about how the EGI system works! Thanks a lot!

The engine is running 100% properly now! Idle up works, and the engine runs on all four cylinders at all revs. And very smoothly, I might add.

The final problem was the air intake boot which was broken. I taped it up and the engine started running properly. (I'll get a new boot, running around with a taped boot is not a good idea)

I adjusted idle to 800 rpm and it runs very smoothly at idle. One final question: the distributor doesn't have any vacuum advance; does anybody know approximately what the ignition timing should be set to? About 14-15 degrees BTDC? With the old carby setup the ignition timing had to be set with the vacuum hose unplugged, it was supposed to be 4 degrees BTDC without vacuum for 98 octane.

Thanks heaps guys, I've learned a LOT about EFI systems in a short time! And it's all thanks to your ideas and advice! If it weren't for you I may not have found all the problems and got them fixed! This is very useful for my upcoming E15ET project too, I know now I can do this kind of a conversion myself! :mrgreen::mrgreen:

Cheers,
Jan

[TurboZ.Dude]

Incidentally, I found out what the ignition timing should be set to. It was written on a sticker on the inside of the hood of a standard CA20E (T12) Bluebird at the junkyard. I was right: it's supposed to be 15 degrees BTDC @ 750 rpm.

So never mind guys, I solved the problem myself!