I rebuilt the 7MGE in this Cressida about 1200 miles ago, it was running like a clock this morning. I fired it up tonight and it displayed a severe miss.
I'm getting spark from all distributor contacts to the wires, confirmed by pulling them out one at a time while the engine was running.
Results of a compression test after it sat for about an hour
1 180 2 175 3 160 4 189 5 160 6 195I put it back together and fired it up to get it up to operating temp again and did it again immediately. During this warm up, I noticed the miss was still there but less pronounced than it had been previously.
1 200 2 180 3 170 4 180 5 170 6 195All the cylinders came up somewhat, some more than others. The shop manual lists 120 psi as the low minimum, obviously they're all over that.
I squired some oil in the two low cylinders 3 & 5, 3 came up to 180, 5 came up to 200. Just for grins I put oil in the #1 cylinder, which was the high of the second test, it went to 210.
I'm a bit concerned about what appears to be a fairly wide gap between the lowest and highest cylinders. Is this normal for 1200 miles out from a rebuild? Also, wondering about how some of the cyls increased up more than others when checked hot. The miss I was experiencing was as if one of the cylinders had flat quit - running rough and an obvious *pap pap pap* at the exhaust pipe where it's normally a quite, silky whoosh. Do any of these cyl pressure differences seem to be enough to cause this?
It's a new engine, hasn't overheated, the lowest cyls aren't adjacent and it isn't losing any water so it would seem a head gasket isn't indicated. It certainly didn't blow a gasket sitting there in the parking lot.
Not burning any oil as far as I can tell. I did the first oil change at around 1000 miles and it's still quite clear on the dipstick after
200 - 300 miles since changing. The plugs aren't new but they look okay, none of the electrodes are fried.Ran like a Swiss watch this morning and ever since the rebuild. Fired it up, and now it's got a problem.
It seems like something that could go bad quick. Maybe an injector? Any definitive way to check with them installed?
Other theories?
Thanks for all input.