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About pfloro

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  • Birthday 05/30/1955

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  1. This is good news... As has been said, half of the problem is finding someone who has real field experience with the system in question. This system had it's idiosyncrasies but it worked reasonably well... Keep us posted.
  2. As "old car fan" said: Stop throwing parts at it. This is a random and expensive way to troubleshoot any problem. <begin soap box> I'm sounding like a broken record (actually it's called a "locked groove") but once again: Check the fuel pressure at the fuel rail. I did some research and too high a fuel pressure (everything else being equal) will squirt more fuel at the intake port during the period of time the injector is energized. The fuel pressure regulator might be malfunctioning. You need a mechanic who can think outside of the box. Remember, this is ancient electronic fuel injection technology (although it was sophisticated for it's day). There is no diagnostic port (OBD II) to which a scan tool can be connected to read out stored trouble codes and real time data. You can't even "flash out" the trouble codes (OBD I) via the Check Engine light because there isn't one. There is no CPU and there is no memory because it's an analog control system. That being said, there are ways to troubleshoot this system with a digital Volt / Ohm meter. I used to have more information about this Bendix/Bosch/Delco system and will search for it. </end soap box> I need another beta blocker now...! Paul
  3. As I mentioned in post #4, consider measuring the fuel pressure at the fuel rail. Won't too high a pressure cause more fuel to be injected during the pulse? I don't know.
  4. As I continue to ponder your rich running situation, two things come to mind: 1) As part of the 1977 emission controls package, your engine has the A.I.R. system. The Air Injection Reaction system pumps oxygen (~20% of our air) into the exhaust ports. This helps the combustion process continue after the hot exhaust gases have left the cylinders. I believe it helps reduce HC more than CO or NOx but I don't know. Making sure this system is working is simple. Rising up from each exhaust port on both manifolds is a steel manifold. There is check valve at the top of each manifold. The check valve (one way air flow) protects the air pump in case there is a backfire. Simply disconnect the hose from one of the check valves and verify that air is flowing at idle and part throttle. The only time air should not flow is during a high vacuum condition (deceleration). To prevent this flow, there is a vacuum actuated diverter valve which reroutes the pump's air into the air cleaner housing. Extra oxygen during deceleration (when the mixture tends to be richer) can cause backfiring because a richer mixture can explode in the very hot exhaust stream. See the attached image of YOUR passenger side check valve... 2) How do you know that at some time in the past, if leaded gasoline was put into the fuel tank. Granted, the restrictor in the gas tank filler neck would have prevented a leaded gas pump nozzle from being inserted but was the car at some point fueled from a jerry can? I don't think it took very long to coat the catalyst honeycomb with lead effectively neutering it. This might be a long shot but... I read that with the analog FI system, the engine ran so clean that a catalyst wasn't needed to meet 1977 emission standards. However, GM chose to install one anyway... Perhaps others can share their thoughts on these two points... You'll find the problem. Paul
  5. Hello MarkV: Your Seville is beautiful...! Let me first make a clarification and then provide some information. The fuel injection system in your 1977 Seville is not a throttle body system but a port injection system. There is a fuel injector at each intake port. Most cars since the '90s have a more sophisticated type of port injection technically called "timed sequential port injection". In these systems, the computer pulses each injector individually in the same sequence as the cylinder firing order. Each injector is commanded to squirt fuel into the intake port during the intake stroke of that cylinder. This technology lowered emissions during idle and low engine speed operation. On a GM V8 engine, throttle body injection uses two injectors mounted in the upper part of what used to be called the carburetor. DFI (Digital Fuel Injection / as GM called it) is sort of a stepping stone between a carburetor and port injection. The two throttle body injectors are alternately pulsed by the computer (both fire simultaneously during cranking). Your Seville uses bank firing to pulse the eight injectors in groups (probably 2 groups of 4). There is no coordination or synchronization between the timing of the fuel squirt and intake stroke of a particular cylinder. This less complicated system worked reasonably well and met the late '70s emission standards. Why all this background? Because... Your Seville uses an early analog electronic fuel injection system. It was a joint venture developed by Bendix, Bosch and (I believe) Delco. The system has no "digital computer" and no built in diagnostics. Specialized test equipment was developed to specifically service this fuel injection system. I suspect this equipment is now as rare as hen's teeth. Finding somebody who understands this technology and is able to service it is going to be a bit tough (IMHO). Your analog system was first offered by Cadillac as an option in 1975 on the 500 ('75 & '76) and 425 ('77 - '79). The downsized 1979 Eldorado (and 1980 in CA) used the Oldsmobile 350 with this analog FI system. I once saw a triple white 1979 Eldorado Biarritz in an Arizona bone yard with every available option and it had your analog FI system. It was a truly beautiful automobile. Beginning in 1980, GM began offering a digital throttle body fuel injection system. Although primitive by today's standards, it had build in diagnostics (OBD I). It was reliable and provided good driveability & lower emissions. GM throttle body DFI was used for many years across all divisions. There are companies who sell systems to upgrade carb equipped cars (Affordable Fuel Injection). Regarding your rich running condition: The first thing I would do is check the fuel pressure at the fuel rail. I suspect it should be around 40psi. If it's too high, more fuel than necessary will be injected and the engine will run rich (high CO). I don't know if there is any easy way to "micky mouse" the system to get it through the smog test. Hmmm..., I wonder if the fuel pressure can be adjusted downward to reduce the amount of fuel being injected into the cylinders. For the smog test, this just might get you through it. Your system must have a fuel pressure regulator but I have no idea where it is of even if the pressure can be adjusted. Below are links which might be of help in understanding your analog FI system: GM Analog Electronic Fuel Injection Cadillac Analog Fuel Injection Please keep us posted, Paul
  6. Thank you Matt for this pearl of wisdom... I feel that taking the time to learn how older systems work gives me a foundation to their evolution to newer systems... Paul
  7. I've waited to respond because I'm not an engine expert by any means. But..., after listening to this noise through a good set of headphones, it just feels external to the engine (as others have suggested). There is a certain crispness to the sound which I think wouldn't be there if it was coming from, for example, under a valve cover, etc. It seems as though above a certain speed, the vibrating engine is causing a resonance triggering some external engine part to hit another part which is too close. As suggested, power braking, a stethoscope investigation and belt removal are all in order to isolate this noise. Since the engine doesn't seem to shutter when speed is increased, I don't think a weak cylinder caused by a valve train issue is the cause of the noise. Please keep us posted. This is an interesting one. Paul
  8. Regarding those concrete walls: I don't know for sure but I suspect they were part of a now defunct water storage facility. Also in this area are partially exposed old galvanized water pipes on the ground and small concrete junction boxes. It's all very curious. A bit farther down the "road", there are two huge water storage tanks (each is ~212,000 gallons / according to the data plates). Wells are part of that facility too. The larger of the two "houses" between the tanks is the pump house / chlorination station... Attached are last year's pictures of the big water tanks. They supply most of the water for the Mount Lemmon community.
  9. Thank you, Victorialynn for starting this post and for everyone's sharing. It's great to see beautiful cars in autumn settings. The two pictures of my beloved 1984 Oldsmobile Toronado were taken in October 1999 in Harrriman State Park. Harriman State Park The park is about an hour north of NYC on the west side of the Hudson and a bit south of West Point Academy. I hiked there for many years when we lived in that part of the country. The Olds was my daily driver for 28 years and 200,000 miles. I do miss The Queen Mary's styling inside and out but I don't miss driving a sofa alongside today's distracted drivers. The other pictures were taken last week on Mount Lemmon (8000') in Tucson, AZ. We do have deciduous tress in the desert...! Enjoy...! Paul
  10. John, Your 'new' Eldorado is just magnificent. It is stunning in every way...! Those wheel skirts really add to it's class. I can't vouch for this vendor but they supply the bumper fillers for your car. '73 - '74 Eldorado Bumper Fillers Eldorado Bumper Filler Installation Keep us posted. More pictures please! Paul
  11. Hello Thomas, Your Cadillac appears to have a couple of different issues. I would put aside all the electronic & electrical issues and fully rebuild the TBI unit first. I am feeling more confident the the very rich running condition is due to the fuel pressure regulator within the TBI unit. Address the TBI unit before concerning yourself with the electronics. The present ECM is not fully functional. Since the 'broken' ECMs allowed you to flash out codes (or allowed the diagnostic system to work), the present ECM has a problem. You need to get an ECM with is fully functional and allows any stored codes to be retrieved either via the Check Engine light or the diagnostic system. Paul
  12. Hi Thomas, Don't let the rebuild of your TBI unit scare you...! It has fewer parts & adjustments than the non-electronic 4 BBL Rochester carburetor which was used on the 1980 Cadillacs (non-California cars). The injectors are simply fuel valve solenoids which are pulsed by the ECM. The IAC (Idle Air Control) is also a solenoid which is pulsed by the ECM to control engine speed as the the engine load at idle changes. The TPS (Throttle Position Sensor) is just a variable resister. You don't need to understand the internal workings of the ECM in order to rebuild the TBI unit. You'll need a digital voltmeter (usually a multimeter which also measures both AC & DC, low current and resistance) to read the voltages in the CCC (Computer Command Control) system. They are not expensive. Here's one on Amazon: Digital Multimeter This type of meter is needed so that the ECM circuits are not 'loaded down' while taking measurements. Carefully open the back side of the connectors to expose the wire side of the terminals. Then you can 'back probe' the terminals with the meter's probes. I've done this many times and it's not difficult. Be careful as the plastic connectors will be brittle after enduring 35 years of heat and cold. You have mentioned that the ECM diagnostic system doesn't work. I think what has failed is the interface between the serial data output from the ECM and the climate control system. In 1981, Cadillac designed the digital climate control system to interface with the ECM. This made it possible to troubleshoot the CCC system without external test equipment. Even without this interface working, you can still 'flash out' any DTCs (Diagnostic Trouble Codes) by jumping two terminals of the ALDL connector and watching the amber Check Engine dash light. Since you have an 'early' CCC system, your ALDL connector should be a five terminal connector located under the dash by the steering column. However, I am not sure where it might be located on your car. Before you attempt to 'flash out' codes, I have a couple of questions: 1) Does the amber CHECK ENGINE light come on when you turn the ignition key to ON? (engine not running) 2) Does the Check Engine light go out when the engine is then started? Code '12' (the first flash is the 'tens' value, the next flashes are the 'units' values / 10 + 2 = 12). Code '12' indicates that the ECM is not seeing a 'reference pulse' from the distributor. A code '12' will always be present when the engine is not running. A code '12' does not indicate a problem. As another example, a code '34' would be indicated by 3 flashes and then 4 flashes in quick succession / 30 + 4 = 34). Once you actually see how the codes are 'flashed out', it will become very clear. After seeing what trouble codes (if any) are stored, I would concentrate on rebuilding the TBI unit. Once that unit is squared away and I hope corrects your rich running condition, we can then work through the trouble codes which exist. Assembly Line Diagnostic Link (ALDL) / 5 pin 1. With the ignition off, jumper the two far right terminals as shown in the picture. "D" is the diagnostic terminal and "E" is ground. 2. Turn on the ignition but do not start the engine. 3. The SES (Service Engine Soon / Check Engine) light will begin to flash a Trouble code 12. One flash, a short pause, and two flashes. There will be a longer pause and the Code 12 will repeat two more times. 4. The stored Trouble Codes will now flash. Each Code will be repeated three times. Write them down. 5. When Code 12 flashes again that indicates that there are no more stored Trouble Codes. Diagnostic trouble codes may be cleared by disconnecting the battery, or removing the ECM fuse for at least 20 seconds. Reconnect and recheck codes to confirm the repair. *********************************** FYI: In the 28 years that I owned my 1984 Oldsmobile Toronado (no TBI unit but an ECM controlled Rochester 4 BBL), I troubleshot the CCC system with a digital voltmeter, an analog tach/dwell meter and flashed out codes from the ECM by using the Check Engine light. Paul
  13. Hello Thomas, You definitely want to service both the pressure regulator (replacing spring & diaphragm, etc.) and the IAC (Idle Air Control). If you car comfortable with removing the TBI unit from the engine and disassembling / servicing / reassembling it, then go for it...! After the rich running condition has been resolved, the TPS (Throttle Position Sensor) should be replaced. This sensor tells the ECM exactly how far the throttle blades are open. However, even a faulty TPS wouldn't cause the extremely rich running condition which you are experiencing. If you purchase the proper rebuild kit for this TBI unit, you can service the the fuel pressure regulator and the IAC yourself. Unfortunately, I can't be of assistance with selecting the proper rebuild kit as I didn't own a GM TBI engine. Be sure to get a replacement spring for the fuel pressure regulator as I don't think the spring is included in most (or all) of the rebuild kits. This replacement spring should be the GM stock type and not a stiffer spring designed to raise the fuel pressure. After looking at the diagram in my post (#24), it seems that if the diaphragm in the Fuel Pressure Regulator Assembly is damaged and leaking, this would result in unregulated full pressure to the injectors. If my logic is correct, this may be the cause of the extreme rich condition. Keep us posted, Paul EXAMPLE - GM TBI Rebuild Kit GM TBI Rebuild Pictures GM TBI Rebuild Video
  14. Hello Thomas, I my previous post (#15), I suggested that you should have the existing TBI unit either rebuilt or purchase a reliably rebuilt unit. Rebuilding a GM TBI includes not only testing or replacing the injectors but also replacing other parts as well. In particular, the fuel pressure regulator section of the TBI contains a diaphragm and spring which can deteriorate over time. The TBI unit also contains the IAC (Idle Air Control). This is a solenoid/spring/valve assembly mounted on the side of the TBI unit and controlled by the ECM. It should also be serviced as part of the TBI unit rebuild. Even though your fuel pressure was low which wouldn't cause a super rich mixture , there may still be problems with the TBI. To rule out these potential problems, a complete rebuild of the TBI unit should be performed. You can certainly use the new injectors which you have already purchased. This was money well spent...! I'm attaching a few images of the TBI unit for clarification. In the drawing, item #5 (Body Assembly - Fuel Meter) is the fuel pressure regulator. Please keep us posted. Paul
  15. Hello Thomas, There may be more than one engine issue to sort out (white smoke at startup) but the main issue is the rich running situation (black smoke)... I am still firmly holding onto my sense that the TBI unit (injectors & fuel pressure regulator) is the source of the rich running condition. With the ignition 'ON' and the engine not running, the injectors are not being energized (pulsed) by the ECM. Even though you don't see any dripping fuel, this doesn't mean that when they are energized, more fuel than necessary is being injected into the intake manifold. I would either have the existing TBI unit rebuilt or purchase a reliably rebuilt unit. The 9 PSI fuel pressure is low as it should be between 12 -15 PSI. The fuel pump (in the fuel tank) is probably weak. However, lower fuel pressure would result in a lean running engine, not a rich condition. I wouldn't make the fuel pump a priority at this moment. Since the outside temperature was 55 degrees F, the white smoke was probably NOT condensed water vapor. It might be either coolant being pulled into the combustion chamber(s) due a head gasket issue or it could be transmission fluid being burned due to a leaky vacuum modulator diaphragm. Your '81 Cadillac uses the indestructible THM400 transmission which has a vacuum modulator. At this point, I wouldn't troubleshoot the white smoke. The fact that the engine was hard to start when cold and required a squirt of starter fluid points (IMHO) to trouble with the TBI. I am certain that the V8-6-4 system has nothing to do with the rough idling and conking out while warming up. If you want to verify this, disconnect both connectors on the tops of each valve cover. These connect to the solenoids which (when energized) deactivate either one or two cylinders on each bank. Startup and idling of the V8-6-4 always uses all 8 cylinders. I suspect the conk out while warming up is due to the 'load up' of carbon on the spark plugs and a mixture that is so rich that combustion just ceases. Regarding your MAP sensor in the picture: There are two sensors attached to that metal bracket. The lower sensor is the MAP sensor which should have a vacuum hose attached to it. The upper sensor (which looks the same) is the BARO sensor (Barometric Pressure Sensor). It measures atmospheric pressure and allows the ECM to adjust fuel and spark as the altitude changes (Pretty Neat...!). It senses air pressure through it's open port so no hose is connected. Once you get this rich running condition corrected, it would be a good idea to replace the spark plugs. They are inexpensive and probably full of carbon due to the excess fuel being fed into the engine. An oil change would also be in order... Please keep us posted. Paul PS: Interesting reading regarding the V8-6-4 engine: 1981 Cadillac L62 V8-6-4 Engine