1993cx

first, i'd like to begin by apologising for posting this. it may have been an old topic by someone else or gone over.

first, i have a 1993 eg hatch cx model. it had a d15 a year ago when i bought it. it had a cracked block. so i dropped it off at a shop and they swapped in a D16a6. It was a few days and it started having idle problems. When i'm at a stop sign or stop light for more than 10 seconds, the rpm's drop to about 500 or 400rpms. starts runnin rough ofcourse and rpms go up and back down tryin. i give it gas while waiting a little bit and starts backfiring from the exhaust and choking. i accelerate from the wait and car just stops like i hit someone and backfires through exhaust badly so i drop it to second from first and have to keep going up. it finaly stops backfiring and throws me back in the seat. it also hicc-ups while cruising and very slow hesitation from start. however, it has never stalled and no CEL/MIL light.

replacements:
i replaced iacv valve
tune up (spark plugs, wires, fuel filter, distributor, cap/rotor
spark plugs were gapped to d16a6 settings
wires and plugs are ngk

it didnt fix the problem, so i took it back to the shop and they re-checked the timing and it was good. so he sent me on the way

i ran a fuel system cleaner (seafoam) by the instructions intake (vacuum), and gas tank. no help

i also cleaned map sensor, same problem, heck, i also unplugged MAP sensor on throttle body, triggered a check engine light and it even stalled it when i gave it gas. so plugged back in ofcourse.

also....... My hatch is running very rich, to the point it makes you feel light-headed. if i stand behind it. it's probably due to my custom exhaust dc headers straight back to zxp muffler. no cat and resonator. and it has been using a lot of fuel i average about 200miles to the tank.

tyked15

is it a full d16a6 motor? cause thats a obd0 motor an you have a obd1 car.. just sayin

fv8s

A block has NOTHING to do with a car being OBD-0 or OBD-1. This swap/conbination has been preformed several times. Try clocking your TPS to .5v at idle and 4.5-5v at WOT. Try bleeding your cooling system also and setting your distributor timing. You can also try spraying intake/ carb cleaner around all the vaccum lines and listen for a change in RPM (to locate a vaccum leak).

1993cx

i've bled the cooling system, replaced iacv. and had the timing re-checked and re-done. i'm gonna see if the tps is out of adjustment. also, im gonna get the map sensor tested. i know the tps has riveted screws, i'm gonna carefully use a dremel if needed to be removed.

90_EX_Civic

true, but the question is, did the shop use the obd1 injectors, or the obd0?

1993cx

honestly, i'm not sure. don't know too much about honda motors. i'm a newb and i admit it.

when daylight hits, i'm gonna test tps, as well as map sensor. hope it's tps over map. can't find the correct map for my vehicle, besides 2 one at a autoparts store 140.00 and at honda 250.00. every since i got this car, i've had a lot of problems with it. from block being cracked when bought, eletrical problems and so fourth.

i will let you guys know how it goes in the morning. thanks for all the help

Former User

Does the CEL work?

Sounds like an ignition system problem. Did you install an aftermarket distributor?

Also check for dirty/clogged fuel injectors.

1993cx

cel does work, just hasnt gone off for this problem. soon as i unplug map and tps sensor cel triggers. replaced ditributor with oem, same with rotor..

test results: TPS .51v idle, wot 4.52v

gonna try and get me a vacuum pump. to test map.

also, this problem is intermitent. times it happens all the time, times it does it every couple hours after not being driven. but lately, it's been happening all the time.

1993cx

i checked the tps while the engine was cold, hope that doesnt matter. i also only tested the (red)(center) wire. ofcourse, if the map is bad thats pretty expensive compared to the tps..

tps: $15.00+
map: $110.00+

Former User

Checking the TPS with the engine cold is fine.

Have you inspected the fuel injectors?

1993cx

for me being a newb, how am i able to check injectors for cloggage? i tried googling it but couldn't find a good way, just symptoms. if you had a link, i'd greatly appreciate it.

Former User

Remove the fuel rail along with the injectors and inspect them.

1993cx

just got back from the shop, fuel injectors are good. not clogged.

1993cx

quick question, if i were to test the map sensor and it tests bad. and if i were to replace it, would i only be able to use the d16a6 map sensor? i've searched many different auto part stores and they have it but it looks completely different than the one i have. my map sensor looks like the tps sensor, just the map logo on it.

90_EX_Civic

im wondering if the shop that did your swap did it right? did they make sure that they used your engine harness from the d15? did they change the injectors? run all the hose's right?

the map for the d16a6 is on the firewall for 88-91 civic's.
and if you map is bad, use another one from 92-95 civic.

1993cx

this shop is very well respected where i live, when i first had problems i took it to another very well respected shop. both of them said nothings wrong. just neither one of them tested map or tps.

90_EX_Civic

well, try that out, and keep us posted.

1993cx

Just to verify, if the map for my d16a6 is bad. I could basically use any map from 92-95 even though its not specifically for d16a6? For example, my old motor in my cx was a D15. I could use that one?

1993cx

Is that correct?