Re: Civic hesitation problem...
 

Matt Ion wrote:
> jim beam wrote:
>> Matt Ion wrote:
>>> JHLorusso@gmail.com wrote:
>>>>
>>>>
>>>>
>>>>
>>>> it sounds like you converted from DPFI to MPFI, in which case a bit
>>>> of wiring was involved
>>>>
>>>> simple run down to check your wiring against
>>>>
>>>> ECU pin component
>>>> a1 inj 1
>>>> a3 inj 2
>>>> a5 inj 3
>>>> a7 inj 4
>>>> a15 inj resistor box
>>>>
>>>>
>>>> run all red/blk wires from injectors back to resistor box
>>>> swap pins from c1 and c2 to b10 and b12 respectively
>>>> run new wire from c1 and c2 into engine bay
>>>> swap out old DPFI distributor plug to MPFI plug (matching colors)
>>>> wire from c1 goes to blue/grn wire on new distributor plug
>>>> wire from c2 goes to yell/grn wire on new distributor plug
>>>> extend TPS plug 6" and swap outer 2 wires
>>>>
>>>>
>>>>
>>>>
>>>> sounds like you forgot to switch the TPS wires
>>>
>>> Both engines (the one that came out of the car, and the new one) have
>>> the same intake systems, the "PGM-FI PROGRAMMED FUEL INJECTION"
>>> throttle bodies and multipoint injectors. I'll tell him to
>>> double-check the wiring, but I don't think that'll be it.
>>
>> it's likely that it is - the tps sensor rotation is opposite on the
>> 2pfi to the 4pfi. the plug and sensors are the same but the wires are
>> reversed as a result.
>
> Except that both the previous engine and the new engine are both MPFI
> with identical throttle bodies...
>
then check the cam timing.

Re: Civic hesitation problem...
 

Michael Pardee wrote:
> "Matt Ion" <soundy106@gmail.com> wrote in message
> news:NE21i.173204$DE1.115546@pd7urf2no...
>> Buddy of mine just rebuilt (with all OEM parts!) a D16A6 with PGM-FI for
>> his '89 Civic (including the appropriate computer and wiring harness). Got
>> it installed, turned the key, engine turned 3 times... and fired right up.
>> Very nice. Idles smoooooth and quiet...
>>
>> But when he gives it any gas, even just sitting in neutral, it bogs and
>> hesitates. Hit the gas too fast, and it just sputters and dies. Do it
>> carefully, and once it gets 1800rpm or so, it works fine. It also seems
>> to idle a little bit rich.
>>
>> Thoughts? Ideas? He's checked for error codes, but it's not giving any.
>>
>> TIA
>>
> It would really help to separate mixture trouble from ignition trouble. How
> about a timing light to see what the timing does when the throttle is opened
> a bit? The timing should advance a few degrees, but not jump fifteen degrees
> or retard a lot. (It may retard some based on the rise in MAP.) Similarly he
> can try adding a squirt of starting fluid into the air cleaner a second
> before he opens the throttle to see if that improves the response - which
> would point to a lean mixture on throttle opening.

Ignition timing has already been checked, but I'll pass on the other
suggestion.

Re: Civic hesitation problem...
 

Michael Pardee wrote:
> "Matt Ion" <soundy106@gmail.com> wrote in message
> news:NE21i.173204$DE1.115546@pd7urf2no...
>> Buddy of mine just rebuilt (with all OEM parts!) a D16A6 with PGM-FI for
>> his '89 Civic (including the appropriate computer and wiring harness). Got
>> it installed, turned the key, engine turned 3 times... and fired right up.
>> Very nice. Idles smoooooth and quiet...
>>
>> But when he gives it any gas, even just sitting in neutral, it bogs and
>> hesitates. Hit the gas too fast, and it just sputters and dies. Do it
>> carefully, and once it gets 1800rpm or so, it works fine. It also seems
>> to idle a little bit rich.
>>
>> Thoughts? Ideas? He's checked for error codes, but it's not giving any.
>>
>> TIA
>>
> It would really help to separate mixture trouble from ignition trouble. How
> about a timing light to see what the timing does when the throttle is opened
> a bit? The timing should advance a few degrees, but not jump fifteen degrees
> or retard a lot. (It may retard some based on the rise in MAP.) Similarly he
> can try adding a squirt of starting fluid into the air cleaner a second
> before he opens the throttle to see if that improves the response - which
> would point to a lean mixture on throttle opening.

Ignition timing has already been checked, but I'll pass on the other
suggestion.