rebuilt 242, really bad gas problem

I rebuilt a 242 for my 88 Comanche, New pistons, rings, bored .10 over, New bearings, seals, gaskets, oil pump, Rods and lifters, New cam shaft and lot more that I'm sure I'm forgetting. Is a renix ECU. After building the engine and getting it dropped n, finally getting it running, I have a major problem. I'm getting 6 mpg and gas is getting in my oil, when I did an oil change after the first couple hundred miles on the engine there was over a quart of gas in my oil. The exaust smoke is blue, I've back probed and checked a few sensors I.e. O2, map, tps I have 37psi on the fuel rail. The timing light reads about 12 degrees advanced but as far as I know there is no manual adjustment for timing. When I put the timing chain sprockets and chain together I made sure the timing marks were lined up. I can answer any questions and would appreciate any advice or suggestions on things to check. Thanks again in advance.

After running the engine, pull the vacuum hose of the fuel pressure regulator. If there is any gas on the vacuum side, replace the unit.

You problem is that your rings didn't seat yet. Hope you weren't trying to break the engine in using synthetic.

That sounds like a lot of fuel contamination in the oil for a couple hundred miles. Sounds like it is something more than piston rings that haven't seated yet.

OP:

Do you have the original injectors? Does it take some cranking before the engine starts or does it start up normally?

I ran conventional oil for breaking in and am still running conventional oil.I've checked the fuel pressure regulator and it is operational.I am using the original injectors with new seals on them.the engine cranks fine, when the engine is cold it runs pretty rough, and bogs down at 2k rmps in all gears. I'll mention also that I can't manually turn the engine from the crank with a breaker bar. I checked main Clarence with plastiguage while assembling and it checked out.

If you have an aftermarket cam, you need to index the distributor by grinding the tabs so that you can adjust it properly. If you haven't done this, see if you can search the procedure.

When it is cold out and running rough, does the exhaust smell like fuel? It sounds like you may have an injector leaking down or partially stuck open.

Do you have a stock camshaft?

jeepkid03 said:

When it is cold out and running rough, does the exhaust smell like fuel? It sounds like you may have an injector leaking down or partially stuck open.

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this.
check the injectors.

timing is completely dependent on load/rpm at the time, and egr status.

I've seen 40+ in a renix ecu.

a bad temp sensor will have a large effect on cold start/run

When I had a renix I bought a HO water outlet and moved the sensor from the block to the water outlet. Seemed to respond much better.

*Most* every time I've seen a really rich running Renix it was something to do with the MAP.

Check that you don't have a bent pin at the MAP connector.
Check that the vacuum line to the MAP isn't cracked or broken.
Check to see that the vacuum line for the MAP isn't plugged into the wrong vacuum opening on the TB.
Checking the electrical connections for the MAP circuit and the grounds may also be necessary. But if the MAP fails to register a base line when the key goes through run on the way to start, it typically has another failure mode.

May be an injector issue, may be a regulator issue but I'd check the MAP first. May even be it is sucking fuel through the charcoal canister and the purge circuit.

Basically what can happen is the ECU defaults to full rich in many MAP failure modes.