"nirodac1" wrote: > OK, I think we have a bit of a misunderstanding here. > > The two opto isolators in the distributor, send a series of > pulses TO > the ECU. > One signal tells the ECU when the engine is at top dead > center. > The second signal tells the ECU what the crank angle is. This > pretty > much determines if the coil is fired, and when. > Failure of either of these sensors and you ain't getting no > spark. > > Using this information (and other things, like air flow, > temperature and > O2 sensor output) the ECU sends a ground signal TO the power > transistor > in the distributor (that would be on pin 6) to turn off the > transistor > which removes the ground from the primary of the coil. As the > magnetic > field of the coil collapses, it generates a magnet flux in the > iron > core, which causes the secondary winding to generate a very > high voltage > (due to the large number off windings in the secondary). This > high > voltage will arch across your spark plugs. > When measuring for pulses on pin 6, it must be connected to > the engine > module, as that module (ECU) is the source of the pulses. > > On a previous post, you stated that you measured 300k ohms on > the > secondary side of the coil. The manual says you should > measure between > 19 and 27K ohms. You might want to check this again. But if > you > replaced the dist, this may not be needed > > Now, if you really want to get down and dirty you could try > this, but be > warned, you do so at your own risk, you could damage something > here. > > If you have the schematic for the ignition system, it would > help. > > Remove the distributor cap. > With all the connectors attached, and the ignition switch in > the "run" > position, ground momentarily, pin 6. > At the same time as you momentarily ground pin 6, grab the > center rotor > of the distributor. If you get a feeling like somebody just > slugged > you, then the coil, and the control transistor are working > just fine. > Seriously though, this will test the coil. Personally I would > hold a > grounded screw driver very close to, but not touching, the > center rotor. > You should get a good spark that should jump at least 1/8 > inch. > > I've used small sewing pins to pierce the insulation of a > wire, then > attach a test lead alligator clip to that. > > The schematic for the ECU shows a transistor providing a > ground on the > lead attached to pin 6 of the distributor harness. So you > shouldn't be > able to damage the control module. The other side of the coil > is tied > to 12 VDC (OBTW did you measure for this voltage) > > I normally use a oscilioscope to trouble shoot these problems. > Meters > are usually only good for voltage, resistance,or current > levels. > > It's strange that the ECU isn't outputting any codes though, > are you > sure it's a steady constant pulse train. > > Did you check for fuel pressure. Cheap and dirty trick is to > slightly > loosen a gas line fitting and see how much gas squirts out > when you > crank the engine (see cautionary note above). > > Good luck > > > > wsnwill wrote: > > "Nobody U. Know" wrote: > > > > Well, I checked to see if I was getting > pulses at pin 6 and > > > all I got > > > > was a steady voltage, unless it triggers so > fast my meter > > > can?t read > > > > it. Does a steady voltage indicate a bad > ECU? Now I am not > > > smelling > > > > any gas where I was before when I cranked > it. Does that mean > > > anything? > > > > Would any sensor not let it start? > > > > > > That probably means the coil is bad. It should be > pulsed as > > > the pickup > > > rotates with the cam. Steady + or - means it isn't > rotating. > > > BTW, a Talon > > > and Eclipse are the same car. I didn't know Eagle > sold a 1.8 > > > talon though. > > > Maybe it was off a Dodge Colt? The 1.8 has almost > nothing in > > > common with the > > > turbo versions, certainly not the coil. > > > > > > > Now my son tells me more. About 3 weeks ago > a belt broke not > > > too far > > > > from home and he drove it home. It > overheated. put new belt > > > on and > > > > started up and every thing ok til this > happened. Now he > > > tells me that > > > > the temp lite on instrurment panel would > stay on every time > > > it cranked > > > > and would go out in about 5 min, but the > guage showed > > > normal. Also, he > > > > said he put injector cleaner in and after > that it started > > > missing and > > > > spittered and sputtered worse and more > often. > > > > > > The overheat isn't good, but it usually isn't as > bad as it > > > could be. There > > > is a simple thermister for the gage and there is a > separate > > > sender for the > > > ECU to read...at least there is on the 2G turbo > version (1G > > > cars have > > > similar setup, plus one for the fans? For 1Gs, > thats all at > > > the radiator > > > too). The best sensor goes to the ECU and the > sloppy one to > > > the gauge. That > > > is to keep the driver from seeing the needle move > up and down > > > a lot. In > > > reality, the temps vary quite a bit during normal > driving. The > > > ECU needs to > > > know this, the driver only needs to know a problem. > In an > > > overheat the > > > sensors can be damaged and wont read correctly ever > again. > > > Normally the > > > gauge one starts to go crazy ($5 part). The ECU > sender is > > > usually better > > > quality ($$$) and doesn't usually get damaged. If > you had a > > > logger you could > > > see the temp and compare it to a cooking > thermometer. It may > > > just need to be > > > replaced. This only affects mileage and emissions. > Not worth > > > it for a kids > > > car. > > > > > > You may want to tell the kid how to deal with an > overheat > > > condition in the > > > future. Tell him to run the heat at full blast, > even in the > > > summer, and > > > coast to a stop with the engine off and the > ignition at ACC > > > (so the heater > > > blower works and the steering doesn't lock up). > It's better to > > > sit for 30 > > > minutes, drive 5, sit again, than to blow a head > gasket. > > > > > > As for the injector cleaner, tell him it is snake > oil. It may > > > have removed > > > some varnish, but they ended up on the plugs. > Modern gas > > > doesn't leave > > > varnish. BTW...how are the plugs? If he did use > cleaner, he > > > could have > > > fouled the plugs pretty badly from carbon in the > pistons. > > > > > > -- > > > Todd Honea > > > > > > > > > > > > > > > .. > > > > Well, I put the new distributor in and still no fire. Plugs > have a > > nice gray coating-not fouled out. ECU still outputting > pulses. When I > > measured at pin 6 it was with the connector off at the > distributor > > cause I took it from the post that the transistor gave the > pulses to > > the dist. > > Tomorrow (actually today, I work nites) I am going to check > all > > sensors to see if one of them is not giving the ECU the > correct signal > > to it can send the spark command. And due to a previous post > I read > > here, I made sure the plug wires were on correctly. > > > > I re-examined the Ecu and noticed what appeared to me to be > wax on a > > few spots on the board but nothing bad. I work in > electronics so am > > familiar with those kind of problems. No burnt components or > bulging > > caps or corrosion. I got a pin out of the ECU so I?m gonna > start > > looking at sensor signals there. If there was something > wrong with the > > ECU would it still give a good self check code 1? I ordered > one and > > they are gonna hold it for me for a day or two. I hate to > easter-egg > > hunt for problems. > > > > I?ll let you know what the results were of checks. Thanks > for taking > > the time to help me. Sorry theis is taking so long. > > > > Bill > >
I disconnected a few sensors (air flow, barometric and idle speed sensor) and tried to start. It wouldn?t but the ECU displayed the correct code failures for those sensors. At least that part of the ECU works. Some more checks. With key on, I measured 5v at center pin of output transistor(green one). I measured 5v at C4 andd at pin42 of IC2. I put a down tower of coil (took cap off) and shorted to ground while trying to start and still have no spark. Cleared codes out of computer, tried to start, didn?t, but no error codes, just pulses (code 1). All voltages are getting to distributor. One question. Does the CRC filter mounted on top of dis do anything other than a tap for the tach. If it was bad would it have any effect. Just curious.
Anyway, I had it towed to the dealership and had them check it out. Guess what....the rebuilt distributor I bought and put in is bad. Pulling my hair out for 4 days and burned 3 days of vacation for a Bad new part. On the bright side, I learned alot about this car. Due to waiting on new new part to get here and dealership not open on Sat, it will be Monday before I will know for sure. I will let you all know.
Till Monday. Thanks.
Bill