Just done a rebulid on my B18c type-r engine. Replaced rings, honed bores and replaced all seals and gaskets, had bottom end balaced and flywheel lightened. Fired up first time (once fuel got through) and has been running fine while ive been running it in. Im running a Unichip piggyback ecu so had a 5000 limiter put on to stop me getting too carried away. Not long after having the limiter put on the car started bogging down at full throttle. Thinking this was a fault with the chip, I took it back to get the problem resolved. It turned out that this fault was not with the chip as we eliminated this out the equation by bridging all the connections. In the garage this problem got worse and worse and would not rev at full throttle and would struggle through the rev range. At one point the engine ran backwards before stalling. The engine will also struggle to fire up sometimes. Idle is spot on.

Diagnosis.............

First of all we checked the pully alignment, which was spot on. We then checked the map sensor and throttle position sensor which were both showing the correct voltages. We then moved on to the Distributor which appears to be functioning correctly. This was all tested using diagnostics equipment. There is a strong spark coming from the coil.

We are completely baffled by what can be causing this. We seem to have eliminated the most obvious items ie. MAP sensor, throttle position sensor, distributor/coil.

Sorry if this seems a bit jumbled but Im just trying to give you all the information I have at this time.

If anyone has any idea what we should try next that would be greatly appreciated.

My thoughts stem along the lines of.........

Plugs
Fuel filter
Throwing the engine in the skip

 

have you checked the o2 sensor circuit? My eclipse had a similar problem w/ an o2 a few months back.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by DragII &raquo;</TD></TR><TR><TD CLASS="quote">have you checked the o2 sensor circuit? My eclipse had a similar problem w/ an o2 a few months back.</TD></TR></TABLE>

Would this not bring up a fault code on the ECU? engine checklight is staying off. Having though about this a bit more today, we are thinking it could be the position sensors in the distributor as this would not throw a fault code. We did not test this when testing the distributor. Going to try another distributor on it tomorrow any way to see if that is the cause... any more suggestions welcome

 

May I suggest the fuel pump, and maybe filter (since it seems to be a WOT situation)?
Looks like you've checked just about everything else.


Modified by zygspeed at 12:29 PM 4/11/2004

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by zygspeed &raquo;</TD></TR><TR><TD CLASS="quote">May I suggest the fuel pump, and maybe filter?
Looks like you've checked just about everything else. </TD></TR></TABLE>

That was considered but it seems to be a timing issue as the engine has run backwards and stalled itself as if the ignition was well advanced. has been concidered tho and will be the next thing to get checked if changing the distributor make no difference.

Its a weird one and has got us stumped big style. Sure it will end up being something really simple and stupid!!!

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by civicsir2 &raquo;</TD></TR><TR><TD CLASS="quote">Sure it will end up being something really simple and stupid!!! </TD></TR></TABLE>

Like maybe the timing belt being a tooth off somewhere, or a cam gear that slipped.

 

First thing we checked