FI to Carb

[rjudgey]

Hey guy's whats involved in converting B20A with FI to carbs, it's not Jap spec ignition it's the early type with vac advance dizzy and std inlet manifold.

Do i just unplug ECU, then change fuel pump for carb pump, carb regulator, and it will work or do i need to add on a aftermarket igntion setup as well??

Stock FI is driving me bonkers i just can't get it to idle smoothly jumps up and down 1000-1200rpm and the plugs are pretty black so it's runningn very rich too, also whats weird the exhaust fumes stink of Gas but thats probably because of the new FPR which i set to 40psi. I removed the cold start valve and put in a known working inlet temperature sensor although that is still 20 years old probably but was working on my firends B20A perfectly before i fitted it? haven't tried water temp sensor as it's a PITA to get at and change. I don't want to spend loads on new sensors when it will cost me not much more to just slap on some webers and get 30bhp to go with it!!

Thanks Rich.

[A20A1]

if it's vacuum advance distributor you can probably use it... just like we can use the A20A3 distributor on the A20A1.

I'm feeling the same troubles as you with my corolla, I want it carbed... the efi system is throwing a code, not sure what it is but my car drives like crap... I had also disabled the fast cold start.

You can run the EFI pump... I'v seen civics with EFI turn down their stock pump with a reg and return line setup and run webers.

[86-accord-lxi]

Why would you rather have carb over fi ? carbs have more problems.

[A20A1]

Maybe stock carbs do...

I dunno, you have to love carbs... and be comfortable with them to want to swap.

[w00tw00t111]

Hey, just thought I'd throw in a suggestion. If you aren't exactly wanting to switch to carbs but, you just want the car to run right then you might try a SAFC. That should work right? To adjust the fuel and then you can mess w/ the timing at the dizzy. Just a thought, if you were wanting to keep efi.

[rjudgey]

Well trouble is not to sure whats up with the injection system, not really got huge experience with FI unlike carbs where have a full on race build with modified Weber 45 DCOE's of which i have a complete tray of every single jet and air corrector you can buy and also different emulsion tubes, chokes and venturis. At the moment my Track car is off the road due to me destroying the engine and gearbox just before Crimbo and the Webers are sitting on it doing nothing so as a cheap fix i though i'll just slap them on the FI car and run that with exhaust and Webers should see good performance increase like 30-40bhp and if i get information that Cat Cams fit B20A's probably even more power on top of that. Looking for an easy 200bhp which should'nt be that hard if their 160bhp from Japan. Also the crusing economy on the highway on Webers is really good and i've never had problems with Webers that wasn't easily fixed as long as their new or nearly new they give pretty long service life.
But what i might try is that resistor trick first as it's a cheap mod and will tell me if it's something more serious than the inlet temp sensor or something else. Can the same be done with the water temp sensor too? Just so i can rule that out? Doesn't anyone know what symptons a dodgy Map sensor would cause?
Thanks Rich.

[carotman]

Check for vacuum leaks. I would never do a FI to carb conversion IMO. Fi is so simple to diagnose I think. Idling problems can be a pain to find but it's still not too bad.

[rjudgey]

I have all new Samco hosing everywhere cause i thought it might be that, the weird thing is it starts up when cold runs perfectly as soon as it's at full temp and you start revving up the engine thats when it starts playing up and no i'm not getting any ECU codes originally had an inlet temp code but changed the sensor for one that supposedly works and reset the ECU and it's never thrown a code since only when i've unplugged sensors to see what happens.

[A20A1]

My car runs better untill it warms up too... :( funny EFI gremlins. :)

[AccordEpicenter]

no codes? If its shitty rich id just get another map sensor but you should check the vac lines going to it (its in the mystery box) Why on earth would you wanna go to carbs from FI?

[rjudgey]

Cause FI sucks i've tried everything now even Chris's resistor trick improved it a little bit but it's still not right when you give it some throttle afterwards. It's driven me mad i've had enough i've yanked the engine wiring off and turned her over theirs sparks coming out the coil to the coil lead that i pulled off so the ignition is seperate to the rest which is good will make it easy to convert. All i need is the inlet manifold to be finished i have the rest allready regulator, pump, fuel hosing, just need to get the old manifold off if anyone has any easy ideas on that one let me know please, if i take the alternator off will i be able to get up underneath the little buts i'm trying to avoid removing the head as i'd like to see what this baby will do without head mods then i can compare when i do re-build the head and do my magic on it.
Oh i'm going carbed because i can and because i don't need no god damn poxy sensors and all i need is my God damn flat blade screwdriver and my box of jets and stuff which i allready have so their don't try and convince me other wise i allready wasted £200 plus pounds on trying to improve and repair this crappy old FI system and i've had it with it final!!

[w00tw00t111]

Hahahaha :rofl: Rich is gettin' pissed I love it!

[carotman]

lol.

There is something wrong with one sensor. It's easy to track down honestly. Just measure the voltage output and resistance of sensors at the ECU. Then, check for vacuum leaks, idle valves acting funny or injectors. Sorry, I just hate carbs. Maybe that's because the stock carb drove me nuts to the point I planned to do an official destroy.

[rjudgey]

should have replaced it with a Weber you would have been happy then!! Anyways did a bit more tinkering as you do in a last ditch effort to get it running bit better and i thought well i'll just try my spark leads of my A20 i know they don't have the right plugs etc but the lengths are about right and i just wanted to try them to see if it was better as Ignition leads were about the only thing i haven't tried.
And well looks like they were contributing to the problem ran my other leads which are splitfire leads and the engine started cold without miss firing and when warmed up seemed definately better idling now, almost to the point i think it might make it to the testing station was easier to run smooth athough i can't seem to get it to idle much less than 1000rpm without it getting the up. But still might change to carb as i need it to be relatively reliable and i'm going to turn it into a track car as the chassis won't last much longer too much rust going on for everyday use and winter use. I can't work out whats up with this EFI tried Chris's resistor mod doesn't seem to make any difference other than cause ECU light to come on!! Might be the TB so i'll put a stock one back on to see if that makes any difference, can the TPS make it run funny??

[A20A1]

If it's off you'll be getting the wrong signal for the throttle angle.