Car drove fine last evening. Have never had an ignition problem. 34k miles. From last evening until this morning nothing was done to the car. This morning it turns over very well but not a hint of ignition. Any thoughts on how to diagnose/cure this problem?
Check your fuses to see if one is blown. Have someone smell the exhaust while cranking. If they can smell gas, then it's either flooded, or has an ignition problem.
Verrel. Thanks as usual for your good advice. I bought a hygrometer and tested the battery. Even though it would crank the engine, the meter showed that it was well into the discharge area. I am now charging the battery. Do you think it possible that the battery would turn over the engine but not have enough charge to get spark to the plugs? The battery by the way is probably five or more years old.
Charged up the battery. Checked the fuses and cleaned each before reinserting. No change. Car cranks over with gusto but the engine will not fire even intermittantly. Do not smell gas at the exhaust pipes. As I said it ran fine when I put it in the garage last night. Above the fuses are box style fuses or relays. Can someone tell me how to test them since there is no visible indication.
Russ -- Did you literally mean that there is no spark (ignition), or did you just mean the starter motor cranks over well, but no cylinder ever fires? If the latter, the first thing to do is pull the (blue?) safety switch plug off at the airflow meter, turn the ignition key "on", and listen for the fuel pump running -- if the fuel pump doesn't run under those conditions, give a shout back and we can dig deeper.
Thanks TR. I have not checked for spark-haven't had time. Its just that the engine cranks just fine but not one cylinder fires. Will do some more troubleshooting and report back later.
Had exactly the same thing happen on my 308. I can only tell you in laymans terms that a ground wire had come off and it was supposed to be attached on the rear bumper. If you have no luuck I can give you my mech. number and he can explain. He said it was harder to find the prob. than to correct it.
Russ: The easiest way to check for potential spark is by clipping an inductive timing light to plug a couple of wires on each bank. If there is no light, you have no spark, if there is a light and you still feel there is no spark then you should pull a couple of plugs to see if they are clean and firing. Z1 Doctor brought up a good point; especially if it was raining when you last drove or if you washed it. Some of these cars develop ground problems either at the digiplex box (in luggage compartment far LH side under removable floor) or at the coils. My guess is that the problem is exacerbated by rain or washing. If you are not getting a spark then I would try attaching a supplemental ground strap to the box. INot sure of your experience with the 328, but to cover all bases, the boxes are easy to see especially if you look at the parts manual. Keep us posted. Mark
Thanks again guys. will be working on the car today and will keep everyone posted. By the way I did an archive search and there is a wealth of information on this problem. 91Tr.can you tell me where the blue wire is that you mentioned. I suspect that it is near the air flow bellows near the air filter. Thanks.
Russ -- I thought someone had previously posted a jpeg of that blue safety switch location, but I can't seem to find it now -- could someone with a K-Jet with Lambda system please post it if you've got it? This threads give some description of the location (posts #3 & #7): http://ferrarichat.com/forum/showthread.php?t=59892 but, if you can't find it, there are more "direct" tests you can do as well -- i.e., posts #2 & #12 in that same thread (and these are the kinds of tests that you'd do next if you fail the "pull the safety plug, turn on the key" test).
91 TR. Found the blue fitting. It is near the airbox. Now I am trying to figure out how to disconnect it. There is a bare wire running around it and it appears that this should be pulled out and the pieces will separate but I am not sure and don't want to force anything. Can someone tell me how to disconnect the blue wire? Thanks.
There's a metal spring clip on those connectors. If you pull that spring clip up (90 deg from the wire path) about half way, it disengages the clip, and makes it easier to separate the connector halves. Push it back down when you reconnect, and the connectors will "click" when connected. You should be able to fit the end of a flat blade screwdriver between the clip and the face (wide) side of the connector. (It's easier to see and practice with the connector on the cold start or freq valve.) On the other hand, the connectors should just pull apart with the spring clip in place -- it just takes a bit more effort. Okay, that might work, too. The spring clip is a "U" with a bit of a half circle indent on the two arms. That indent fits into a gap in the outer shell, and fits into a slot on the inner shell. Displacing the clip pulls the indent up onto the outer shell. Pushing in on the base of the "U" causes the arms to spread out a bit. Either one should disengate the indents from the inner shell. (edit) - I stand corrected -- the spring would pull completely off this connector -- pushing in on the exposed part spreads the arms and allows you to remove the connector. -- photos on the way. If you haven't tightened down the clamp holding the air box on the intake, the easier way to check for pump operation is to turn the key on and lightly press down on the AFM plate -- the pump should run when the plate isn't at the rest position.
Photos as promised. You can see the indents on the connector, and that they disappear when the clip is compressed or removed. (Some day before the next server crash, somebody ought to collect all these sample pictures and diagrams and assemble the ultimate engine bay coffee table photo book. ) Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login
Thanks DGS. I was wrong when I said that I had located the blue fitting. The one I was speaking of is the one that goes into a tube that goes into the top of the plenum. I will try the same disconnect procedure with the one that you photographed. By the way I did depress the large valve in the airbox with the ignition key just short of the start position. The pump did not activate. Am now going to pull the rear wheel drivers ide and check the pump and the accumulator per what I found on some earlier posts. Thanks again. Will keep everyone posted.
That's the cold start injector. I don't know if you're working in a quiet garage, but you should hear relays clicking in the absence of the fuel pump. If not, try disconnecting the blue safety switch connector. If that works, then you're safety switch may have gone bad (or out of adjustment) ... which isn't too likely, but possible. If you pull relay "s", pin 85 should be grounded unless you disconnect the blue connector or push on the AFM plate, when it's open. Pins 85 and 87a should be +12 volts when the ignition is on. If you jumper from either 85 or 87a to pin 30, the pump should run with the ignition on. If that works, check your safety ground circuit or the relay itself. If jumping at relay "s" doesn't work, check relay "r" for operation -- it should click with 12 volts across pins 85 and 86 (and should connect pins 87 to 30 when active). If you pull relay "r", and jumper from pin 87 should have +12v with the ignition on. If not (and anything else that's ignition switched works -- such as gauges), then you may have a problem with your relay board. If nothing operates off the igntion, check relay "u" (carefully -- pin 30 is hot wired to the battery). If you have ignition power, and jumpering pins 87 and 30 on relay "r" doesn't cause the fuel pump to work, then you have to see if you have voltage at the pump. (With the wheel off). Another way to check the relays would be to swap "s" with "d" or "e" (headlamp lifting motors), or "u" or "r" with "l" or "m" (headlamps). If you can then start the motor, but the headlamps don't work -- you have a bad relay. The subject of the pump safety circuit has come up often enough, I thought I'd attach an interpreted schematic - hopefully a bit clearer than Ferrari's. Image Unavailable, Please Login
To all. Here is what I have determined: 1. I disconected the blue safety fitting and also depressed the large valve under the air filter. In neither case would such actions cause the FP to run. 2. I checked for voltage at the FP relay ans there is twelve volts at the relay. 3. I swapped an identical relay with the FP relay. Still would not work. 4. I put a wire between the top and bottom of the FP relay as directed but that would not cause the FP to activate. 5. Looks to me like it is the FP but I defer to the experts. 6. Is there a way to check the FP without taking it off which presumeably means draining the tanks? 7. Final comment. Over the last year I frequently smelled gas after putting the car in the garage but nothing was dripping from the car that I could detct. Could this be an indication of a FP going bad., By the way this troubleshooting is far less onerous with all the good advice that I am getting!!! Thanks again to all of you. I forgot. DGS where to you find the numerical references to the relays? The relay fuse identifier in the inside of the fuse box cover doesn not identify them by letters.
You can check for voltage at the pump (under the rubber boots). Or inject power across the pump with the regular leads disconnected. In the back of the owner's manual or on the wiring diagram. Image Unavailable, Please Login
I did my 328 fuel pump not long ago. It is really easy and here's the link just in case. http://www.ferrarichat.com/forum/showthread.php?t=70515&highlight=328+fuel+pump I also was able to drain the tank by disconnecting the SS braided hose from Accumulator to Filter-- this may be one way of checking positive operation of the fuel pump? Also, I believe you should be able to change the fuel pump without draining the LH tank, so long as you are able to block the hose end (5/8" ID) once you disconnect it from the Fuel pump inlet or clamp the hose tightly, or both.
Although the direction of this thread is fuel delivery-related, have you checked for spark or the digiplex ground wire as yet? If you don't have a timing light to clip to the plug wires, remove a plug, reattach the ignition wire, ground the plug to the valve cover and crank the ignition. If you have spark you'll see it. Best of luck.
Or simply attach a spare plug to the lead and ground with battery jumper cable. That way you don't have to remove a plug. Have someone crank engine while you hold it in your hand by the jumper cable. This is a standard test I used whenever something won't start.
You'd want to be careful about holding 20KV in your hand, particularly if you're standing on concrete in leather soled shoes. Rubber soled nikes or an insulated floor is a bit safer, and the jumper wire is insulated, but you still want to err on the side of safety. High voltages will leap at you ... literally. Air itself is a conductor with sufficient voltage per inch -- which is how the spark plugs work in the first place. But if there's no fuel pump, there's nothing for the spark to light. One caution on fuel pump testing -- Bosch fuel pumps are cooled by the fuel flowing through them. Running them dry will burn them out in a hurry.
At this point, if you have not already done it, you should probably run jumper wires from a 12V and ground source directly to the fuel pump connectors. This test would determine if the pump itself was working. There could be a wire problem between the relay and the pump or it could be the ground at the pump itself. I believe you can get at the fuel pump connectors from underneath the car without taking the wheel well out. Good Luck, Mark
Mark. I have the car up on jack stand and can feel/see the electrical connectors for the fuel pump. Are you suggesting that I jump the 12 volts directly from a car battery to the FP and see if it energizes? Would an alternative test be to check the resistance between the connections on the fuel pump? If so what ohm reading should I look for? Thanks again.
With the pump connected, you're measuring both the pump and the car wiring. The best test is to disconnect the car wiring, and jump an independent 12v source (such as another battery) directly to the pump leads. If it doesn't run at that point, you have a bad pump. If it does, then you can look for the harder things to find, such as a loose connector or shorted wire in the harness.
Thanks DGS. I have the wheel of and can see the FP but the leads are away from my line of sight so getting them disconnected will be tough unless I am missing something. Any thoughts or just get in there and do it. I have done the diagnostic tests from the fuse board and the airflow disconnect test. This also included swapping relays with s and r. Nothing will activate the pump. I also note that I do not hear any relays clicking when I do the airflow disconnect-the blue wire-as I was told in this thread should happen. However virtually everything else electical works just fine. I have a continuity tester and am trying to detect current at the FP with the FP relay jumpered between 87 and 30 as I recall. Haven't been able to detect voltage but I am not sure that I am doing the test correctly. Do you have a foolproof (me the fool) way to get 12 volts into the pump circuit so that I can test to see if it is getting to the pump. Preferably with the ignition off. Thanks.
