3SGE BEAMS Swap - No Spark

[GlanzaAtHeart]

HI team,

Asking on behalf for potential help.

We have 1990 Rev 1 SW20 G-Limited that's had a redtop BEAMS engine swapped out from another running, driving Rev 1 SW20 G Limited. Engine harness, motor, gearbox were swapped.

The motor turns over but doesn't get spark. It has fuel. The coils have power but we don't have access to an oscilloscope.

We jumped pin TC to earth and while the CEL turns on at IGN, it doesn't flash when jumped?

Potential problems I have thought about:
- ECU damaged?
- Loom damaged?
- Body harness causing no spark? But unlikely.

Could anyone possibly provide some insight or some things to check? Thanks in advance team.

[GDII]

No spark can be due to the cam and crank sensors not outputting a signal or the wiring being damaged.
The cam sensor wiring gets soaked in oil due to the sensor leaking internally and this can lead to brittle wiring. Oil makes it's way all the way along this wire and it can make its way all the way to the junction block and if that has been removed it can make it's way to the ECU.

[GlanzaAtHeart]

Thanks for the reply Phil, yeah definitely a potential problem.

I did check the resistance coming out of the crank sensor and it was identical to the resistance coming out of mine (Both same part #) but I didn't think to check the wires between the sensor and ECU. I will also check the cam sensor, will do it this weekend.

[GDII]

There are 4 elements to these sensors.

Crank position sensor
1. The crank shaft timing belt pulley teeth. If one breaks off it messes with thing. I don' think it's this but you never know.
2. The wiring. You have an NE+ wire for the signal to go to. NE- is shared by the cam position sensor
3. The shielded element of the wire has to be grounded at 1 end (ECU in this case) for the main wire but the engine block for the short length to the sensor.

Cam position sensor.
Same for this but it has a single trigger on the cam that only gets picked up every 2 crank shaft rotations.
It has a G2 instead of NE+. NE- is shared and earthing is important for the shielding.

[GlanzaAtHeart]

There are 4 elements to these sensors.

Crank position sensor
1. The crank shaft timing belt pulley teeth. If one breaks off it messes with thing. I don' think it's this but you never know.
2. The wiring. You have an NE+ wire for the signal to go to. NE- is shared by the cam position sensor
3. The shielded element of the wire has to be grounded at 1 end (ECU in this case) for the main wire but the engine block for the short length to the sensor.

Cam position sensor.
Same for this but it has a single trigger on the cam that only gets picked up every 2 crank shaft rotations.
It has a G2 instead of NE+. NE- is shared and earthing is important for the shielding.

Thanks for this - It really helped. We checked this today, and continuity between the wires is fine :/ So it's not the wiring between the sensor and the ECU that's the problem, and the plugs + pins on the sensors were replaced recently.

We tried using my coils and spark plugs, still no spark, and a spare working redtop ECU we borrowed. Odd thing is that even with pin TC jumped, no CEL would flash. We tried unplugging AFM, TPS, Coils and still no flash.

The plan from here is hand the car over to an auto electrician.

[GDII]

Are you getting power to the coils? And are they grounded?

[GlanzaAtHeart]

Are you getting power to the coils? And are they grounded?

Yeah we are, and yes they're grounded (it wasn't me who checked this haha, I didn't wanna be responsible after last time), Logan and I had a good look through things and couldn't find much.

CEL not flashing still stumps me, and to be honest the loom is in such poor condition that it really wouldn't hurt from being re-done completely.

[GDII]

Always hard to diagnose when the wiring harness isn't built well.
IDK if you'd want send it my way for a full strip down and check to ensure the wiring is correct. Cheaper than sending it to an auto sparky.