1. I replaced a broken ECT (plastic connector was loose and rotated freely) and cured a hard-start condition. I've not before seen a) loose ECT connector; or b) a hard-start caused by a bad ECT. Anyone seen this?

2. Car is a 1992 with a white-label 561. Owner said it always (3-4 years) started and ran "OK". I thought the 561 was replaced by the 951 when the cold-start valve was discontinued - 1991? I thought you could replace a 561 with a 961 but not vice-versa.

Before the fix: Owner lost coolant and overheated the motor. He replaced the motor with a bare-block 1986, using all of the 1992 components except things he replaced with new..

The car had a hard-start, motor cold, from the 1st time he fired it after the swap. Always the same pattern:
- Fire on 2nd-3rd rev and then die
- Crank and crank and crank with an occasional fire on one/two cylinders
- Fire, run 5 seconds, idle down, die
- Crank and crank and crank with an occasional fire on one/two cylinders
- Fire, run 10 seconds, idle more slowly, die
- Repeat a few times; if the battery wasn't drained by now, crank some more
- Finally it would stay running on 2-3 cylinders, then catch and smooth out.
- It needed to idle for 2-3 minutes before driving or it would stall when put in gear
- It ran on the rich side but not excessively so.
- Warm starting: it would fire on the 2nd/3rd turn of the engine and stay running.

Had a code 1-2-3 (ECT signal fail). I cleared and it didn't come back so I wondered if the code was caused by the overheating.

The car needed some maintenance anyway so we tested and/or swapped in new/good: MAS & air tube; vacuum hoses & flame trap; main fuel pump (was noisy), filter & in-tank pump, fuel relay; plugs, rotor, cap, wires; air filter; power-stage amp; CPS; FPR was newer and line had no gas; O2 sensor in range; throttle cleaned & sensor adjusted & tested; IAC removed, cleaned, tested; fuses removed, fuse ends and brackets cleaned. Compression is good. During engine swap: grounds on engine were cleaned; intake manifold gasket replaced; timing belt & idler replaced.

Hard-starts I've seen from too much fuel - eg. leaky injector(s) - have been a different starting pattern: crank and crank, 1-2 cyls fire, then 3/4, then it runs rough and smokes a bit before it smooths out. The hard-start above seemed like fuel starvation or an electrical problem.

(Aside: The black ECT I installed didn't show the correct resistance but it was the only spare I had. Maybe operator error. We'll know if the car runs rich and/or shows a 1-2-3 code.)
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240 drivers / parts cars - JH, Ohio