xide_12

Its a d16z6 engine with the eagle/vitara combo and a basemap from phearble. Before I started it up I put a little oil in the cylinders and primed the turbo. It started up right after like 1 turn over, but it idled rough at like ~500 rpms. the rpms slowly dropped until it stalled out about 2 minutes later now I cant get it started. oh and the fuel pump eventually stopped priming.

the bad:
fuel pump wont prime anymore
cranks but wont start
no fuel
code 0 on cel

checked:
spark is great
compression is 105 120 110 115 (low compression ratio on unseated rings)
timing belt is perfect
all fuses in cab and under hood are good
gm 3bar map sensor is getting 5v
fuel pump will prime if i jump the main relay
battery is charged
visually the ecu looks perfect (no burn marks or anything)


I suspected it was the main relay so I tried resoldering and it didnt work. so I replaced it with another one and tried resoldering that one and still no luck.

also the bolt for the ground on the thermostat housing snapped off. so I extended the ground to the chassis and still doesnt work. is it bad to do this?

Im running out ideas anyone got any?

Former User

Double check hood ECU fuse 31 and then do this:

(ACG fuse = dash fuse 24)

xide_12

just did most of them except I dont have a test harness or a spare ecu. But i did find:

- 0 voltage between a25 and a26
- there IS voltage between b1 and a26

so it looks like it boils down to the main relay, but not the yel/blk shorting out. Could the main relay some how throw a code 0?

Former User

Good job finding the problem.

The fact that b1 has voltage tells you that the main relay is fine.

Note that the Yel/Blk wire from the main relay eventually branches to a25 and b1 before reaching the ECU. Your tests tell you that the branch to a25 is broken. Run a new Yel/Blk wire to a25 from the good branch of the Yel/Blk wire near b1. This should solve the problem.

xide_12

I just noticed this but the a25 in that diagram is wrong, its directly above a26 not to the left. just tested the real and a25 also gets voltage

so its starting to look like a bad ecu but I dont have a spare on to test. could it just be a bad basemap chip?

Former User

I never noticed the error.

You need to do all remaining tests in the diagram. You don't need the test harness. For example, just disconnect ECU connector D and test for continuity to body ground at terminals D19 and D20 in the connector.

For tests where all ECU connectors must be plugged in, just back probe the terminals in the connector or scrape away a tiny amount of wire insulation to do the tests.

SOHConthis

well i say if u have spark but no fuel id say straight wire the pump and then try it.

xide_12

my multimeter doesnt have a continuity tester, but it can measure resistance between d19/d20 and ground. and if there is resistance there must be continuity? sorry Im terrible with electricity its probly why Im only having electrical problems.

it seems weird though, I dont have the egr sensor and I havent touched the throttle position sensor. The map sensor is getting 5v and outputting 1.6v like it should and Iv checked to make sure the wires are spliced to the right ones like 30 times. oh well ill check it out again

Former User

Continuity = low resistance

A reading of 0-100 Ohms is generally considered as an indicator of continuity. Post your Ohm and voltage readings.


Your engine does not have an EGR system, so don't worry about testing it. Did you disconnect the MAP and TPS to see if the solid CEL (code 0) turned off? You need to do all of the tests in order in the diagrams.

xide_12

they were both getting 5v, and 355 ohms each.
The only test I havent done is to swap it with a know working ecu, I dont know anyone who has one, but everything else has passed so far

and yes the solid code 0 stayed on when I disconnected the sensors

Former User

If the tests found no problems, it's time to find a good ECU to swap in.

ej_purple

hcheck your main relay for tha fuel pump. and the idle is to low because of your throttle cable. so check does thangs and let me know aite man

xide_12

damn I was afraid of that. would I haveto convert the injectors and map sensors back to stock in order to test a stock p28?

Former User

I think you could just hook up the P28 to see whether CEL code 0 goes away and the engine starts. If so, turn the engine off after it starts.

xide_12

alright ill find one, thanks for the help