79 cad fuel sys analyzer tool

[Jim Smith]

I am trying to locate an electronic fuel injector system analyzer, cad tool j-25400 for my 79 seville. The car was  equipped to sell in Calif only in 79.  There is no air pump but has an o2 sensor and a special calibrated electronic control unit(ECU) for fuel injection control. The ECU is the same for all states I believe, except for Calif with the o2 sensor it is calibrated differently. I bought the car a couple years ago from over in the San Francisco bay area where the emmission requirements were less stringent than they now are and it will not now pass the testing done here in the central valley. The emmision problem is too high a co2 level. It seems local independent shops and even the local cad dealer are reluctant to tackle the problem as they dont have the analyzer or techs old enough to have hands-on experience with the system. I have the 79 cad service manual which gives a detailed checkout procedure of all the system sensors and the ECU using the analyzer. Im reluctant to turn this over to just anyone to learn on and would prefer to do it myself if I had the analyzer. Wonder what happens to tools like this when the dealers get rid of them after gathering dust back on a shelf somewhere. I have checked eBay and nothing so far. Its a nice <60k miles seville and certainly not ready for the crusher. Would appreciate comments, even how were you dumb enough to get in such a mess per my wife, but it was just too nice a car to pass up.   My apologies if this should have placed in another section.  Jim

[Tod - North TX CLC]

Jim -

I dont claim to be an expert on these cars, but the first thing that you mention raises some questions.

To the best of my knowledge, all of the F.I. Sevilles would have been equipped with an A.I.R. pump, and air injection heads.  The fact that your does not have the pump would indicate that some work has been done on the engine.  In most states that do not require emission testing after 20-25 years, these heads are often replaced with the non-injection heads.  This may well be the source of your problem.

If the coolant temp, air temp, and exhaust oxygen sensors are working, the EGR valve and sensor are functioning as designed, and the car is running well, then there is little adjustment of the ECU that will compensate for emmissions (assuming that the MAP sensor in the ECU is hooked up and functioning properly).  As you can see from the manual, having the analyzer does little good except to diagonose a failing part such as a sensor, TPS or injector.  One thing to keep in mind, several owners have suggested replacing the Catalytic converter if yours is still the original - may not have an impact on your problem, but is has been suggested.

To answer your question, no, I am not sure of where to locate the analyzer.  I seem to recall seeing one on e-bay some years back, but based on its limited usefulness, I did not follow the bidding.

Please let us know what you discover.

[Jim Smith]

TOD -

Thanks for the reply.  If you have a Factory 1979 Cadillac Service manual please refer to pages 6C-61 and 6C-62 (Fuel System). There the "closed loop" system built for 79 sevilles sold in Calif only is described. The Exhaust Oxygen Sensor and the specially calibrated ECU and their operation is described. No air injection was provided using the closed loop control. The next 55 pages of the manual are devoted to the description, diagnosis and testing the components and system using the analyzer. You are correct in that the analyzer will only show whether the components are working or out of  proper calibration and it could be that the cat. converter might be the problem. The co2 in the exhaust is almost double the Calif limit so not sure how much a defective converter would contribute to that.  The car starts, idles smoothly, runs and performs very well with no indication of problems. The car gets a couple miles per gallon less gas mileage than the identical car I had years ago when they were new. Based on the way the car performs I have tentativley ruled out the injectors as being being dirty or defective but that may not be true. The ignition system is all in good condition and operating properly. Any way Im scheduled next Monday to take it over to a shop associated with a Cadillac wrecking yard where the owner says he has a technician who works on these older Cadillacs all the time and is familar with the fuel systems.  Dont think he has an analyzer so will be hoping for the best. Will pass on the results.  Jim

[Tod - North TX CLC]

My Seville manual is on loan to a member in Houston, so I cannot refer to the section you mentioned, but I will take your word.  I was basing my information on my 1980 Eldorado which has the CA closed loop 350 EFI system, and does have the AIR pump and heads.  I have a total of 4 of these engines in 3 Sevilles and an Eldo, and just mentioned that in all my dealings with these cars, I had never run across one without AIR.  Since the Eldorado has the CA closed loop with AIR, I assumed that the Seville would also have the AIR pump - my mistake.

My cars became exempt from Emission testing in the past couple of years, but on the last test, each of them were at least 50percent below the threshold for emissions.  The only time that I failed a test was a few years back when the line from my AIR pump to the Cat converter was leaking on the CA Emission Eldo - once I replaced that and all was well.

Keep us posted on your results, and if I glean any information that may help, I will let you know.

Tod

[Jim Smith]

Tod

You thoughts on air pump for the 79 Seville may yet be correct.  I checked further in the service manual and on page 6E-7 (emision controls)it says all vehicles built for sale in Calif have the air pumps.  Pages following show the pump for the Seville mounted up front on the top of the engine with hoses running across the top of the engine to the distribution manifolds connecting to ports on the heads. I checked the heads on my engine and found the manifold connections were plugged with hex head plugs some of which had some of the original factory blue paint on them. On my original 79 Seville which was a Calif car also I had to replace the intake manifold gasket but dont remember the air pump which I would have had to remove to do the job.  An acquaintance who worked as a mechanic for the Cadillac dealer in Seattle during the late 70s and 80s says he remembers the Seville at least in 79 having the Olds 350 engine but he cant recall for sure about the air pumps. Also some of the Cateras had chevrolet engines he says. Little wonder GM has problems when their customers pay extra for a vehicle and find out later about all they got extra was the nameplate. Not all were buying just transportation they were car people who thought they were buying a car. Anyway still unsure about this air pump.  A list of items shown on the emission report done on my Seville shows the air injection item checked off as N/A.   Maybe will know more next week. The state requires here in the cental valley that the cars must run on a chasis dynamometer at 15 and 25 mph while checking emissions. Im wondering what is required in your state.  Perhaps to avoid boring others on this forum with all the nitty-gritty details we should e-mail directly.  My e-mail address is   nsj62@inreach.com     Jim

[Jim Smith]

Tod

The Seville passed the emission test with no problem after the shop I mentioned previously replaced the ECU. All fuel system sensors checked out ok. The technician says the 79 Sevilles sold as new in Calif were not equipped with an air pump but did have the O2 sensor and specially calibrated ECU. He says the service manual statement that all 79 Cadillacs built for Calif is incorrect and that 76, 77  and 78 Calif Sevilles did have the air pumps like the rest of the states. My original statement that CO2 was high was incorrect, it was the CO that was the problem. Jim