b18a1 civic swap help

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i have a 93 b18a1 in a 93 civic, when i first got it (already swapped) between 2500 3000 rpm its was doggy/ sputtery but would clear up as long as im over 3000 well this last week while driving hwy spd it dogged down serious power loss i push the cluch coast and rev it a lil and it clears up continuing to drive fine, next day same prob and now when im not on the gas after it warms up idle starts goin to shit then stall... fires right back up, stall... unless im giving it gas, driving is decent again until i let off the gas, ive been told coil or vac leak, but idk i need advice, and yes im new to honda's and know i need to find more info but ive been reading forums for 2 weeks n need specific advice... your help and time is much appreciated:confused:
 
As honda civics use a D-jetronic derivative injection system a vacuum leak would cause a high idle not stalling. Check your timing and ignition system. a coil going bad or a funky cap and rotor could cause this but I am leaning more towards a sensor or fuel issue. Do you have a CEL and have you checked for codes? Try cleaning your throttle body and idle control motor.
 
Well.....first and foremost....check engine light on? (Important to clarify)

Could be vacuum, MAP, TPS, IACV, Distributor, or a combo of things.

Vacuum can be checked with some starter fluid or carb cleaner. (making sure to be careful and mindful of the amount you spray)
 
the cel is on however being a complete honda noob im having trouble figuring out how to get the code, everything says look for an led but i cant find it so i know to use the dash, but i have a p72 obd1 in there and there isone set of wires with i'd say ten prong clip with jumpers in it ill post a pic thats where im confused with that part. i just got the coil so im hoping that will do it, but with my luck..
 
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well it wasnt the coil... brand new one in and it still does it... anyone know a link for good vaccum line routing in the b18a1... as i look more at mine, whoever started this swap is a jackass
 
So....."it was the coil".....that tells me you No Longer have a Check Engine Light ...CoRReCT?

If you don't know where the service plug is, it's under the dash very close to the passenger kick panel. There are two plugs that aren't plugged into anything. The smaller one Is the service plug. If you close the circuit with a paper clip or piece of wire, the CEL will flash like Morris Code for you. Long flashes are multiples of "10's" and short flashes are increments of "1's"

Check all vacuum lines for cracks and such...if there seems to be no visible leaks, then you can check for a leak. When car is running at running temp....lightly spray some starter fluid or carb cleaner around the vacuum lines (there's not that many). Listen for the Idle to change....this will let you know whew the leak is.
 
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noits still doing it after replacing coil still throwing a cel but ill take a look in the am for the plugs i need to get these vaccums figured out i pluged one with my finger and it started running better and there are some that arent hooked up... also ive read maybe the iacv but im not finding it in my chilton book, there are a few things i need help identifying,well its a mess, and will be more of a project than i thought but oh well its good to learn new things
 
Vacuum lines not hooked up? I had a B18B1 swap and there were only 3-4 vacuum lines. Some were coolant lines. But I think the B18A1 lines are a little different (never owned one)

You are (most probably) spinning your wheels (in terms of figuring out the solution) without getting the numerical engine codes. It's like putting together a baby's crib and refusing to use the included directions (been there...done that lol)

The picture of the plug you took.....that is not the service connector (is it off the Hondata ECU?)

The service connector is under the dash....right of the glovebox. It's a small two wire plug.
 
the wires from that plug run into my harness with the rest that are connected to the ecu ... im an idiot ive been lookin at it the whole time just took your overly simple explination to find the plug lol.... CEL FIRST CODE "6" 2nd was a "9" 3rd was a "14" and finally a "21"
 
6: Engine Coolant Sensor

9: #1 Position Sensor (aka crank positioning sensor)

14: Idle Air Control Valve (IACV)

21: VTEC control solenoid.....and thats like "what the hell....your motor ain't VTEC....what ECU are you running???"

ECU code is on the opposite side of the plugs ....numerical with a bar code.

Maybe check the codes and double check the counts on the codes.
 
i have a p72 from a 94 gsr i got lucky its written on there lol but i did check the code also to confirm. should i just look at a new dizzy since ive done the cap coil and rotar already not much left i can swap in that for the code 9 and yes the 21 threw me a little about the vtech thing ive been trying to research it nut not much luck
 
and i did triple count each code im kind of paranoid like that hense me freaking about the vaccum lines which i made a neat diagram hoping someone can look and say its all good or no wait that one goes there
 
IMHO.....you need to find A P74 or P75 OBD1 ECU (92-95 Integra LS/GS)

Some people have claimed to run non-VTEC motors with VTEC ECU's but others claim its idiotic and wont run right. I've never tried but I know you'll always have a check engine light for VTEC.....and you don't have IAB's (secondary butterflies on GSR IM's) but I dont think it throws a code :what:

Also.....code 9.......I don't think it's the crank position sensor.....it's just a cylinder sensor.

But some of these codes could be a non-compatibility between ECU and motor/components/sensors/etc.
 
I'll try and make this look like something beyond thread crapping. :)

Looking at the wiring on the fuel injector plugs, and the dash pot without a line connected to it - What I see is an abortion. You have inherited someone else's mess to clean up. It doesn't work? No surprise there.

Me, I would get the wiring schematics and clean it up, soldering and heat shrink on all connections. Replace all vacuum lines, etc. Probably thermostat and coolant lines as well.

The wiring work I see is so shoddy, if it works today, it will fail tomorrow. You are going to be chasing ghosts through that thing on essentially a continual basis.

I'm not car bashing here or suggesting you're a dumb ass for buying it - I'm bashing the prior workmanship. If you got it for a decent price, and the motor is in ok shape, then it's certainly worth cleaning up.

Good luck with it. ;)

EDIT: I looked back through your thread again and see you referred to the "Swap Engineer" as a "Jackass" and are looking for the vacuum line routing diagrams. You need the wiring and vacuum routing tech data from both a suitable donor vehicle for the engine, and also the set for the target car. You're on the right path.

My 1991 hatchback wasn't swapped when I bought it, but the wiring was all phuked up from some moron doing a DIY alarm and DIY stereo installation. Also parts and screws were missing everywhere. It took a while to clean it all up - many runs to the Honda dealer parts counter and lots of wiring repair.
 
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IMHO.....you need to find A P74 or P75 OBD1 ECU (92-95 Integra LS/GS)

Some people have claimed to run non-VTEC motors with VTEC ECU's but others claim its idiotic and wont run right. I've never tried but I know you'll always have a check engine light for VTEC.....and you don't have IAB's (secondary butterflies on GSR IM's) but I dont think it throws a code :what:

Also.....code 9.......I don't think it's the crank position sensor.....it's just a cylinder sensor.

But some of these codes could be a non-compatibility between ECU and motor/components/sensors/etc.
I've ran the DOHC ZC non-VTEC engine in my hatch on a P28 VTEC ECU and it runs like shit. Throws a CEL for the VTEC solenoid and that's probably is why it runs shitty. When I put the correct ECU/MAP in it, which is P29, it woke it up big time.
 
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