2seater

Barney reminded me of another possible tool to use when trying to diagnose a stubborn problem, and it costs exactly nothing. Most sensors have a backup safe operational setting in the ECM. Simply disconnect the sensor and start the engine and see if the behavior changes, possibly for the better. The engine will start and run with the cam sensor, MAF, O2, inlet air temperature, water temperature, knock sensor and I believe even the TPS. You will get a check engine light for most of them but it can be a useful diagnostic tool. Of course it needs to operate for a while if it is temperature related. I would try the MAF sensor first.

This the best depiction of the Teves pump and system but it lacks the internals of the switch. The holes may just be needed for assembly?? I just don't know.

I don't know what the small holes are for, but they do extend into the body of the switch but not necessarily in a straight line. I wouldn't think that sitting still or driving would make any difference to the o-ring unless heat or vibration has some effect? The system pressurizes to 2600+ psi in motion or not. Maybe it just takes some time for the fluid to wick out along the threads which are a close tolerance.

Thanks for the insight🙂 I have a cottage on the Embarrass river 13 miles west of Shawano upstream of Pella. Small world.

I am not sure of the purpose for the holes in the switch body outside of the o-ring either. It looks like they may be some sort of weep hole to indicate a leaky switch before it works its way to the electrical, somewhat like the weep hole on a water pump, but I do not know if that is the case or not.

Yes, that switch is a beater, but it works fine for my test rig. It was in a pump that galled up the threads so I partially filed off the threads to allow it to be used as a test subject. It is not used in a road car.

This from another thread regarding the coil to plug wire connections. There are different diagrams online for different engine installation orientation. This is correct for both the Magnavox and Delco style: The Magnavox coil pack wiring scheme is: Top 6 - 3 5 - 2 4 - 1 Harness connector end How this translates to the Delco vertical arrangement. Top 6 3 5 2 4 1 Harness end It does not matter which plug wire is connected to the specific terminals as long as they are paired correctly on each coil.

Okay, you inherited an existing problem. You mentioned the coils were changed, but what style ignition? The factory setup is the Magnavox style with the three coils in a single pack, the later Delco is three separate coils. The ICM below are different and specific for each. If the standard Magnavox style, check the ICM below the coilpack for melted potting material oozing out, a sure sign the ICM is on the way out. If the ECM was changed, was the original PROM moved to the new ECM? What was the source for the replacement ECM

This is what the o-ring fit looks like on the beater brake switch on my test rig. No leaks and the switch is installed just snug, only slightly more than hand tight.

I am curious about this issue but I don't have a solution at this point. It seems you have done everything properly and better than most. I would try your selection of o-rings and let them stand in a jar with your chosen fluid to see what happens physically. I think EPDM should work but an online search has mixed results which I would guess you have found too. Is there any chance they are slightly different size than the O.E. rings? Any sort of burr or nick inside the housing for the switch?

At the stated mileage, the hard parts in the engine should be good, unless they have been replaced/adjusted in the past. It does sound like it could be a spark timing issue as Ronnie pointed out. Too much advance will do that as well, or something wrong with the order. It is not uncommon to get a couple of the rear plug wires reversed, #2 & #4 for example. They point towards each other to an extent. Were there shims under the original starter mount and were they reinstalled? Is the starter the standard large body style or the gear reduction starter with the smaller motor? Did this engine ever start and run well? You made reference to it sitting a long time, but was it in your possession before and after the storage? Pretty car by the way.

Good advice above. Have you checked the onboard diagnostics for any codes and is the check engine light on? I saw the list of items checked but could you put some numbers to it, like compression and fuel pressure? Does fuel pressure hold for a time after the engine stops? It sounds like it runs pretty smoothly in the video, but the starting is not a smooth rotation from the sound of it. It has a catch, or hesitation, in the sound like one or more cylinders has more compression than the others, or the starter has a bad spot. When it starts to run poorly, is it at a similar engine temperature, or when it goes closed loop which can be found in diagnostics. I am not super familiar with the touch screen cars but there is a loop indicator on one common screen. The engine starts on the ICM and then the ECM takes over.

Welcome. In case of multiple issues, it is usually best to post a separate thread for each. That said, I do not understand the nomenclature: central shaft and causing things to seize???

Bench racing or not, throwing out crazy or impractical ideas provokes thinking and conversation 👍 The Reatta fuel tank is a purpose built and probably not worth trying to modify due to its design. A trunk mounted fuel cell would seem most practical. It’s just me, but working out exotic exhaust would seem way down on the list😊 Maybe consider rear mounted turbo’s instead of mufflers? A V8 is easier to muffle than fours and even sixes. Just $.02

Yup, and they fire with reverse polarity to each other🤔

The diagram above is arranged as a RWD would be installed as well as no reference to wiring connection 😊

Nope, your first diagram is correct as long as the harness connection is at the bottom relative to the diagram. It does not matter which terminal is connected to each coil as long as they are paired on the correct coil. They both fire at the same time as one complete circuit.

I think it is the squared style of the Allante that makes it look wider. The specs say the two cars are almost identical width, height, legroom but a shorter wheelbase for Reatta even though overall length is greater.

I don't know the results of any actual swap that has been done, so I don't think there is a known conclusion? The comments, at least from my point of view, was that there are substantial differences but the overall form factor looks feasible. I am not up on the various Cadillac types, but doesn't the Allante have many similarities to the Reatta, where the STS is a four door sedan? It is certainly a more sophisticated suspension. If it indeed will swap in, it is pretty much just four bolts plus parking and service brake lines/cables to try it. I have aged out trying things of that scale.

You are in uncharted territory but I admire the creativity🙃 Is there enough material to run bolts through the coils, into the baseplate and sandwich the ICM in between? Actually I am not sure the method of clamping everything together really matters as long as it is solid mechanically and electrically. As far as I know, both greased and non-greased has been used successfully. Any question of longevity is probably hard to answer since the time spans are long.

It sure is a busy rear assembly, especially compared to the Reatta. I wonder if weight capacity has anything to do with it? The Reatta is a pretty heavy car, despite its size, but about 65% of that is up front. Maybe it's an illusion but the unsprung weight looks like a lot more.

I agree completely about the need to heat sink most electronic components. This is one of those things that is an open question in my mind: Is the mounting bracket on the engine, warmer or cooler than the ICM itself? I have never done so, but always intended to measure the temperatures of the components to see what's what. 🙃

The factory baseplate is a solid piece, no reliefs or vents for airflow. To grease or not to grease gets bandied about and I do not know if it is good or bad. I do know, I have never seen a recommendation to add grease in the FSM or found an original in the parts yard that was greased? When I have my turbo engine installed, I relocate the ignition assembly by rotating it 90* for harness clearance to the exhaust piping. To do so, I made a plate that supports the ICM which extends out beyond the factory mount, but sideways, to provide the ICM studs something to connect to. This is the Magnavox style, but it has operated in that configuration for going on two decades. Oh, and no grease used.

I would guess the large knock count bursts triggers the spark retard, ED16, which will tend to reduce power. Bad tank of fuel? Before the knock bursts, does the O2 reading tend to drop off to the lower numbers, like below .45, indicating a lean condition? ED19, short term fuel and ED20, long term fuel may also give a sense of what the ECM is trying to adjust if the fuel delivery is suspected.

If you mean using the Magnavox ICM AS the baseplate, I don't believe that will work. The spacing of the fasteners for the coils is in the wrong place to mate up to the Magnavox coilpack screws. I do believe it would be very doable to make your own baseplate with a piece of 1/4" aluminum barstock about 3 1/2" x 5 1/2". Drill and tap for studs out the bottom and tap on top for the six coil mount screws. The thread doesn't matter as long as you have mating screws.