Got Spark, Got Fuel.. Got No Go....

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drasticdezignz

Member
Hey,

okay, I did the DX to Si swap.. I got spark... I got fuel... no ecu codes, everything is hooked up in the right place... but the engine won't fire... It cranks over, sounds healthy, but she won't go....

the engine was pulled out of an 89 Si from the wreckers with 7o,ooo Km's on it. The engine hasn't been started in a while, but it turns over easily...

I have tried using engine start to get it going and it seems like it wants to start going, but it doesn't pick up. Now, has anyone had this problem, or any suggestions that I should do to try and fix this problem???
 
spark + fuel should = a running car...

how do you know youre getting spark at the right time?
how do you know youre injectors are functioning?
 
Get someone (or buy the guage) to check your compression! You have yet to mention that (since it is a vital part in the starting a car....lol...jk man)
 
Have you checked your ignition timing? If its off too much it wont start, but you'll get spark.
 
How exactly do I check the timing when I can't start the car??? I know I can adjust the distributor, but how so? It looks to be in the middle of the bracket, but do I advance it or retard it?

The spark does seem to be a little weak though... how do I improve this???
 
As for the injectors.... I know I am getting power to all the injectors, and they are giving off good resistance... there is pressure in the fuel rail as well... Are there any other checks I can make to make sure they are spraying???
 
Check to see if your sensors are plugged in correctly. A common mishap is the tps and map are switched. Check the compression. Are you sure your getting fuel into the cyclinder. Maybe the injectors arnt firing??
 
Definetly check the compression. It happened to me, I bought an engine and then put it in only to find out it had no compression. It would crank over fine.
 
Originally posted by drasticdezignz@Jan 3 2004, 11:50 PM
How exactly do I check the timing when I can't start the car??? I know I can adjust the distributor, but how so? It looks to be in the middle of the bracket, but do I advance it or retard it?

The spark does seem to be a little weak though... how do I improve this???
Click to expand...

Loosen all 3 nuts just sufficiently to shift the distributor.

Facing the distributor side of the engine...
Clockwise = Retard
Anti-clockwise = Advance

No ecu codes. I suspect something is wrong with your main relay. Have it checked regardless. However, I remember you mentioned taking power directly from A15 which means a total cut off from the main relay. You should have taken your power from the dpfi injectors black/yellow wires instead as it is a tried & tested practice and you can also easily diagnose your actual problems.
 
okay, but I wasn't getting power to the two dx black and yellow wires... The test I have in the Haynes manual says that the relay at start up will activiate the fuel pump if it is working correctly....and it does.... but it doesn't run power to the two Dx injector wires....
 
Originally posted by drasticdezignz@Jan 4 2004, 01:13 PM
okay, but I wasn't getting power to the two dx black and yellow wires... The test I have in the Haynes manual says that the relay at start up will activiate the fuel pump if it is working correctly....and it does.... but it doesn't run power to the two Dx injector wires....
Click to expand...

From the PGMFI circuit diagram, the yellow/black wire to your resistor box is actually spliced to both A13 and A15 which is also connected to the main relay (i.e. + joint). It is not just directly connected to A15 only. In either way, you don't just cut off a connection on the ecu just to power your injectors. If you said your injectors are getting power, are you sure you are getting the right amount of power with just A15 only?

I did the very same swap as you a week ago. I just joined the yellow/black wires from my primary and secondary dpfi injectors and soldered to the resistor box yellow/black wire. You already mention there was no power to your two yellow/black wires. There must be power to these wires, if not, there must be an open circuit along it somewhere, which is very rare unless you happen to change your original harness. Your car was running fine before the swap right, you should have power to the two yellow/black wires.

Solve the problem in a continuous chronical flow. From Problems A-C. You don't solve C when you haven't solved B. B might give you a different equation for C.

Just don't get too frustrated during the swap, it can only mess things up. Do it as simply as possible. This dp-mpfi swap involves one of the most tedious re-wiring than any other swap.
 
Well.... found my problem....

3 injectors where clogged.... fuel wasn't reaching the chamber..... time to get new injectors!!!
 
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