ThomasBorchers

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Posts posted by ThomasBorchers


  1. Hi to all!

     

    After the winter I wanted to start our 1913 6-54 roadster, I charged the batteries, they have 6.36 volts each. So fully charged. Wenn I press the button between the seats, then depress the clutch pedal, the starter not start to turn the engine. So I checked the voltage at each of the batteries when I pressed the button ( the voltage drops just a bit 0.02 volts ) when I depress the clutch pedal to turn the starter, 3 batteries drop to 6.25 - 6.20 volts. But one of them... ( it is #4 ) starts to boil and the voltage rises to 16.5 volts! 

    Has someone an idea what the problem could be?

     

    Thomas


  2. Hi to all!

     

    I am frustrated. I have worked and changed a lot of parts at my 1981 Cadillac Fleetwood with DFI. But now : The engine will not start.

     

    I have already a long topic here (  http://forums.aaca.org/topic/280562-1981-cadillac-fleetwood-dfi-location-of-oxygen-sensor

     

    The main problem was : Too rich running engine! It was not possible to read the error codes. ISC not working.

     

    I did this in the past :

     

    Put in new injectors

    Rebuild the fuel pressure regulator

    Adjusted the TPS

    Changed the MAP Sensor

    Checked the TPS

    Checked the engine coolant sensor

     

    Since the ISC was not working I disconnected it finally and set the engine idle speed around 800 rpm. So the engine run not bad but on the street, it had some power “holes”. It seemed that some ignitions were not there.

     

    OK, so I decided to order a new ECM and ISC. Today I built in the ECM and ISC. At first, I wanted to check the error codes. I switched the ignition on and then the heater fan started to run. I switched it off, pressed down the “OFF” and “Warmer” button. After a short while, these two dots were shown. And that’s it… no 88 to check display or codes. After a short while, the fan started again…

     

    I decided to start the engine and it started right up. It seemed that the mixture was not too rich but one or two cylinders worked not. I thought, that this was a problem from the last drive and started to check the spark plugs and some were wet.  I seemed that somewhat was working in the ISC as the engine was running.

     

    After cleaning the plugs, I wanted to start the engine, warm it up to adjust the ISC as described in the shop manual.

     

    But now, I have the problem, that the engine will not start. Here and there is an ignition but will not run. I checked again the plugs and some were wet. And I can clearly smell the fuel of the throttle body but there is no leak.

     

    I hoped, with these new parts I have the solution but at the moment I am more far away from the solution as before.

     

    Today I had the chance to start again with cold weather but after a short while the engine run slower and slower because one cylinder after the other was flooded by gas and several spark plugs were wet. Mostly the ones in the middle of the cylinder heads.  With just one injector, the engine is running but with two, in warm condition it goes off. This is a new situation since I have the new ECM and ISC.

     

    The ISC is not moving but it is ok, I have checked the motor and the switch of it.

     

    Has someone an idea?

     

    Kind regards

     

    Thomas


  3. Hello again,

     

    well, in the meantime I am a bit more familiar with the DFI system.

     

    As Larry told me, I have checked the TPS adjustment. The voltage was too high for the idle speed. To adjust, I had to remove the TBI body, drill out this small welding spots which block the “adjustment” screws of the TPS. There I found out, that the cam of the throttle cam has a bit too much clearance in the TBI body. But I have replaced the TBI housing as it was.

    Then I tried to adjust the engine at 400rpm but this was not possible. The lowest speed I can set is 600rpm. Under this, the engine shuts off. Perhaps this is the result of the throttle cam play, don’t know.

    So I set the voltage of the TPS at 600rpm at 0,6 volts which should not be too much. So actually from this view, the mixture should not be too rich.

    I tried to do the adjustment as described in the shop manual with ISC and TPS. But the ISC is not moving. Since I know, that the motor can work, if it has voltage, I think the actuation from the ECM is not working as it should. Probably…

    I removed then the plug of the ISC, set the plunger to an idle speed around 800rpm. The idling was ok now, the exhaust was perhaps a bit black but not that much as before. Then I accelerated the engine and the was a “hole” in the acceleration, was not really possible to speed it up. When I went slowly back to idle, it run again rough and with more black smoke as before.

     

    At this point I decided to order a new MAP sensor since this part is also responsible for the mixture.

     

    Today a have installed the new MAP. Well, actually it is like before but I mean, that it now accelerates better as before. But going slowly back to idle, I have than again a too rich mixture and the engine shuts off. When I then shut of the ignition, wait some seconds, start again, the engine runs again better with good idling and just a little bit black smoke or perhaps it is just blue from oil.

     

    At the moment I come to the result, that the ECM could have a malfunction and need to be replaced. ( again… ). What do you think? It shows no codes, the ISC is not working and then the rich idling…

     

    I am sorry for my English but it is hard to say all this in a foreign language.

     

    Kind regards

     

    Thomas


  4. After this day, I must say : The solution is close. With too rich mixture idling, I started to remove the whole ISC. I opened the nuts and then of course the idle went down. And… the mixture went leaner. So I got a good, not too rich idling. Hmm, I checked if the motor of the ISC is working but it seems not. I have tested the motor of the ISC outside the car. It worked but not really smooth. So I opened the ISC and cleaned it up with new lubrication. But I don’t understand this : If fully extended, the gear lose the contact to its spindle and it is not possible to retract because the gear turns now free. I don’t if inside is something missing to stop the motor at the end.

    I guess, that something is not working correct between TPS, ISC and mixture… ?

     

     

    OK, now, since the engine was idling good, I have problems to accelerate the engine. When I push the gas pedal, the seep rise up but then it seems as the mixture is now too lean to pick up speed. With faster push down the pedal, the engine shuts off.

     

    At the moment I am happy that the rich mixture is gone but have to solve the other problem.

     

    What I would like to know :  How much volt about should I measure at the ISC connector?

     

    Kind regards

     

    Thomas


  5. Hi Larry,

     

    today I tested the wiring of the coolant sensor. Seems that the sensor is ok, the resistances look ok. The wiring from the plug of the sensor to the plug at the ECM is also ok.

     

    I cleaned up again the spark plugs and started the engine. Hmm, funny… the first minute it seemed, that everything is working, no black exhaust. But after ca. a minute the idle drops a bit and black smoke came again out of the exhaust system. But it seems, that it is not that rich as it was before. I waited the whole day and tried again with cold engine. Was the same… in the first minute it was ok, than again black smoke as it was in the morning.

     

    And it seems that I have a problem with the ISC. Looks not so, that it is working. But I have to check this tomorrow with my shop manual. To adjust the TPS, I have to remove the TB and so on. A thing for tomorrow…

     

    By the way : With engine running, the gas tank went empty and as the fuel pressure went down, the idle speed went up since the mixture was leaner and leaner. Of course just to the point, as the gas tank was really empty.

     

    Regards

     

    Thomas  

    • Like 1

  6. Hi Larry,

     

    thank you. I will check this out. Ah, but I remember I checked already the TPS, the voltage was 1 Volt.

     

    What I have seen today : When I disconnect one of the fuel injectors, it runs of course leaner. But : If just the drivers side is running, the mixture seems to be ok, a bit too rich but hard to see a black smoke. When I use just the passengers side injector, it runs too rich with black smoke. Actually the mixture should be the same? Could this be a a note of the problem?

     

    Kind regards

     

    Thomas


  7. Hello again,

     

    today I had the chance to rebuild the fuel pressure regulator. I haven't seen something broken old parts, but the old spring is longer as the new one.

     

    Now... it seems that the engine runs richer as before... hard starting, heavy black smoke... :(

     

    Well, since I put in new parts, the engine runs richer and richer... makes it sense to change now the TPS?

     

    Kind regards

     

    Thomas


  8. Hi Ivan,

     

    after testing a while ( the carb ist still in place at the car ), the funny thing is : You can turne the mixture screw as you like, it makes no different. Even when the engine is runnig, you can pull full choke : Makes no different! If the engine is running, it has full power, has a smooth idle and the spark plugs elektrodes look great. Could be that the engine goes off at a traffic light. If this happens : It is not possible to start the engine again. Just if you use some start spray...

     

    For me at the moment... it is a mystery.

     

    Kind regards

     

    Thomas


  9. Hi to all,

     

    after restoring our 1955 Oldsmobile Super 88 with Hydramatic ( was not on the street for 20 years ), I had the problem, that the transmission went into reverse as it shall, but not into a forward gear. After shifting lots of times, this problem is solved. So I went on the street. But.., there was no shifting up. I browsed through the shop manual at the trouble shooting but found not exact my problem. Just : Transmission operates only in 2nd speed ( DR range ) or only in 3rd and 4th speeds. As a cause stands there : Sticking valves in inner valve body or governor. And as correction : Completely disassemble and inspect valve body assembly and governor assembly.

    Has someone an other idea or is this the way I have to go? And does this mean, that I have to remove the transmission?

     

    Kind regards

     

    Thomas


  10. Hello again!

     

    I was some day on the roads in Sweden and now back to my Cadillac. Thank you for all the thoughts.

     

    Today I have first cleaned up the spark plugs.

     

    Then I started again but from the start of course again, heavy smoke. I wanted to check the vacuum from the TBI unit at idle speed, my gauge shows there -400 mBar. I don’t know in what I shall it to convert to US standard.

    I have read in the shop manual, how to check the TPS, but for this I had to disconnect one of the injectors, then the engine run nearly ok. A bit black smoke but the engine run. After a while I thought, that the idle shall drop down but it will not work. Was still at the same speed with warming up. At this, the voltmeter shows 2 Volts, connected to the ECM. I have removed the ISC from its bracket to lower the idle speed. So I guess that I had the 375 upm but not really sure since I don’t have a tachometer which works for 8 cyl engines. At this idle speed the voltmeter shows 1 Volt which actually is too much, the book says 0,5 Volt. But is this a reason to run much too rich?  

    After this, it seems that the ISC is not working.

     

    To all your questions :

     

    To Larry : Well, the diagnostic system starts not with 88 as it should, it shows just two dots and then nothing. As I changed to the old broken ECMs then it worked as it should.

     

    To Paul : I already have a multimeter since I have often to do with car electrical problems.

    Yes, I have seen it, that it is possible to open the connectors at the back. Perhaps just one time, as you said.

    On page one you have already written about the possibility to check the codes by “check engine” light. And I tried this already but the light will not start to flash. The ALDL is under the dashboard in the middle.

     

    1.) : The check ignition lamp is already on, if I switch on the ignition.

    2.): When the engine is running, it will not go out.

     

    As I have written on Page one, as I used the both broken ECMs, then trouble codes 14 and 19 were shown. I know the reason for these codes : Someone has put a jumper in the connector of the coolant sensor and the relay of the fuel pump is removed and there is also a jumper wire that the fuel pump pumps all the time. I have connected the coolant sensor again.

     

    Well, that’s it for the moment.

     

    Kind regards

     

    Thomas


  11. Hi Paul : Thank you again. Well, I am working at old cars since 20 years, So I guess, that I could manage to remove the TBI unit and so on. I am not really familar with these electronic things but changing parts, I can do it.

     

    @ misterc9 :

    I have checked the vacuum hose at the MAP. Actually I wanted to disconnect the hose at the MAP but this was hart to reach since there are all the cables from the ECM connectors. So I decided to disconnect the plastic line from the hose which goes into the TBI unit. But first I tried to suck a bit the the line which goes to the MAP. I did it very carefully but there was no resistance. I had a closer look to the MAP and have seen : There was no clamp at the hose at the MAP. I put one on it and then there was a resistance, as I sucked at the line. OK, I started the engine but ran very rich. But I ran just on 4 or 5 cylinders now, since all sprak plus must be dirty now. So I had now no chance to check if there is vacuum at the hose from the TBI unit. This will be the next step, but first cleaning the plugs.

    I would need an adapter for my OSB scnanner but I am not sure if I can read there something, since the ECM diagnostic system will not work.

    @ Larry : Is it possible to check the voltage with out a scanner, just with a voltmeter?

    Kind regards

    Thomas


  12. Hello Paul,

     

    thank you, for your explanation. Well, I thought, since the pressure was not to high, that it is not necessary to chnage the pressure valve. But seems, that I was wrong.

    Somewhere else I have read, that the TP Sensor could be the problem, sending the wrong position to the ECM. As  you said, that the problem could be also in the TP Sensor.

     

    Well, do I need now a full TBI unit or can I change the TPS and fuel pressure valve by myself?

     

    Now it is so, that it seems, that the engine gets more fuel as before I changed the injectors. But with this, it starts great.

     

    Kind regards

     

    Thomas


  13. Hi all,

    today I have installed two new injectors with all these o-rings and gaskets. The engine started now by the first two turns ( after standing still for a couple ogf weeks ) but now immediately black smoke, not after a while.

     

    Weather : Sunny with 83°F

     

    So all my hopes are gone in these two new injectors...

     

    Thomas


  14. Hi Paul,

     

    thank you very much for your words and thoughts. Yesterday I disconnected the battery over night and also the four plugs for the 8-6-4 system. I started today again and I let the engine idle with the higher idle speed, which the engine has after cold start. A long time there were no or a very few black smoke. Then I depressed the acclerator pedal for lower idle. Then it startet again the usual black smoke.

    But this time, I had not these dropouts in the idling.

     

    Well, I have to see, that I can get the injectors and regulator for a resonable price here. But I have a good source, just 5miles away.

     

    Kind regards

     

    Thomas

     

  15. I have seen now, that in the plug which goes from the coolant sensor to the ECM was / is a jumper wire. I pulled it out and checked the voltage, it is 5.7 volts. I plugged in the plug in the connector to the sensor but there was now change, still black smoke. And it will be darker black smoke, the hotter the engine is.

    The sensor hat a resistance about 1.8 kOhms

     

    The fuel line in my Cadillac has already a tap so I checked the fuel pressure and it is about 9 psi.

     

    I have also found the O2 sensor and pulled the plug but it runs still much to rich.

     

    When I have the ignition on, I looked at the injectors if they drip fuel but they don't.

     

    In an other forum, I have read, that someone had a problem with a vacuum hose and the MAP sensor. So I had a closer look to my sensor. It is a plastic style set like this one on the right side : 19838020rt.jpg

     

    But just the lower one has a vacuum hose, not the upper one. Is this correct?

     

    For me it seems as when the injectors deliver always the same amount of gas at idle speed. On the road, the car runs not bad. But at idle... in short time, I have a black cloud on my property.

     

    Hmmm....

    1981 Cadillac.jpg


  16. Today, I started the engine again from cold condition. Outside it was 55 °F, the start was hard, I used finally a bit easy start spray. OK, then the engine run, I had a look at the exhaust. Was light white smoke. Then the smoke were more intensive but still white.

    Sometimes it seemed, that the engine will stop but run again. This made the engine several times and then at one time, the smoke was black. Then the engine stopped by itself after a minute. But it was possible to start it again and had now again the black smoke…

    Could it be, that if it seems, that the engine will stop, that it has something to do with the 8-6-4 system?

    By the way : I wonder why I don’t have this instrument, which shows how many cylinders are working.

    Now I will try to check the coolant sensor.

    Regards

    Thomas


  17. OK, an update : I changed to the other old ECMs and they work really not. Seems that one produce a to advanced spark ( if they can do it ) and the other one makes a similar trouble with a backfire in the carburetor. But both ECM show me the code "14" and "19". I tried to clear the codes but this was not possible.

     

    But : As I started with the good ECM, the mixture seems to be ok. But after a while ( perhaps 3 minutes ), suddenly the engine run worse and again black smoke.

     

    That's what I found out in the meanwhille.

     

    Thomas


  18. Hello,

     

    and thank you for all the answers. A lot to read.

     

    At Larry : I own a OBD 1 and 2 scanner but have just the OBD2 plug.

     

    At Paul : Very interesting, I have to check all this out. No, I don't have this supplement. I have this big, silver Cadillac shop manual and the wiring diagrams.


    OK, I have to read now, and will come back later.

     

    Kind regards

     

    Thomas