2.7i Perfect idle, runs very rich with throttle

[WildBill]

Just finished a 731 head swap on my 86 eta with 173 ecu. Has 19lb Mustang injectors, 325i TB and manifold, longtube headers, m30 afm, sssquid chip tuned for 19lb inj and afm.

Test drove the car two days ago and it ran fine, had good throttle response and no stuttering.
Yesterday, drove the car to a muffler shop and it started driving fine, then progressively ran richer and richer until it couldn't be given any throttle or it would backfire, and give no acceleration at all. At idle it runs perfectly fine, stable and air/fuel seems normal.
Going to swap my afm with a known working one this afternoon, any other suggestions?

[WildBill]

Also, brand new spark plugs were black when I pulled them. They don't even have 20 miles on them.

[EatsHondas]

Is the chip for the M30 AFM?

[WildBill]

Yes, the chip is tuned for m30 afm and 19lb injectors.

[packratbimmer]

I would ask if the chip is designed to match the flow rate of the 731 head. Correct me on this, but the 885 would flow a higher volume of air. Not sure if it would make enough of a difference to necessitate a specific chip???

I had a challenge with tuning my M10 after putting my ported Metric Mechanic (MM) head on my stock 1.8 bottom end. MM does awesome work BTW - I was warned about the challenge!

[WildBill]

I suppose that could make a difference but my 731 is port&polish. I don't see how that could change driving it the next day though, even unplugged the battery to reset any adaptation.

[WildBill]

If I give the car any throttle at all above idle, it starts backfiring and then dies out

[E30 Wagen]

how do you know it's running rich?

[WildBill]

how do you know it's running rich?

Shooting flames and sputtering whenever throttle is moved. And you can smell the unburnt gas out the exhaust

[WildBill]

Swapped in the stock eta afm and tps and it worked fine

[WildBill]

Well, found out the problem was none of the above. The locating dowel on the camshaft snapped, causing the timing to be off until today, when it spun the pulley but not the camshaft. Valves hit pistons :(

Tearing the head off now. F&$@

[packratbimmer]

Ah man that's horrible - sorry!

[WildBill]

It sucks man, 731 head is destroyed at cylinder 5, valve snapped off the stem and bounced around wreaking havoc. Piston disintegrated from it. There goes about a grand :/ now I'm trying to decide what to do next. Finding a 731 head is very hard in the US.

[WildBill]

It sucks man, 731 head is destroyed at cylinder 5, valve snapped off the stem and bounced around wreaking havoc. Piston disintegrated from it. There goes about a grand :/ now I'm trying to decide what to do next. Finding a 731 head is very hard in the US. And I don't have the money for another right now.

[packratbimmer]

Pics? Is the combustion chamber destroyed?