You can often experience this light together with an EPC light or a similar one. The check engine light is the first thing you will notice on your dashboard when the car is in limp mode. Here is a more detailed list of the most common symptoms of limp mode: 1. The most common symptoms of limp mode are check engine light, reduced engine power, RPM limit, or stuck gear. Many car owners do not take enough notice of the engine light, and therefore the engine computer sets itself to limp mode, shuts off the turbo boost completely, and puts a max RPM limit to 3000 RPMs to be sure that you won’t blow or damage any engine parts.īut how do I know that my car is in limp mode, and how can I recognize limp mode? Limp Mode Symptoms Overboost may damage your pistons or other internal parts very fast, and therefore, the ECU limits the engine power. The limp mode often reduces the power and limits the engine’s RPM to drive your car to a workshop without damaging the engine.įor example, if the engine control unit detects that your turbo boost pressure is 2.0 bar when the maximum boost pressure should be 1.3 bar.
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When the engine or transmission control unit receives a very faulty parameter from the engine or transmission, the car will go into limp mode. Limp mode is a security function for your engine and transmission. If anyone there has any ideas, information or experience with this type problem, I sure would be grateful for help.Can you Bypass Limp mode? What is Limp Mode? I have contacted the local Nissan dealer, and they disavow any knowledge and desire to tackle this, so in my shop it still sits. However, when ignition switch off, the ECM stays powered up (checked for 15 minutes) until ECM physically unhooked from harnesses. Once powered up, turned screw to get codes, got 2 relating to the A/C. Ignition on, ECM would not boot even with power on the proper pin at the ECM, unless a momentary ground of the #6 red wire at the ECM, from the EFI relay. Checked and found no pulse on - side of coil. Dealer won't work on it and Nissan USA knows nothing and doesn't want to help.Ĭylinder head temp sender (from a trouble code)Ĭhecked output from dist to ECM, got the 360 signal and 1 other signal (assuming #1 cyl) with a good oscilloscope.Īll grounds I could find with help from Alldata and an 84 300zx troubleshooting disc.Ĭondenser between coil from and ground dist baseĮngine cranks normally, no spark from coil secondary. Turn on the ignition key and the ECU does not bulb test or give error codes unless you momentarily ground terminal 6 whereupon it will give codes (only AC errors) and then won't turn off when the switch is turned off. Coil, Distributor and all associated hardware is new or good. We have a 1984 Nissan 300 ZX with no spark.
#Nissan 300zx ecu diagnostic lights dont work manual#
The procedure is in any after-market manual and if you don’t have one, I recommend Haynes. Any other info you have could be helpful so feel free.Īlso, if you have the time, check your ECCS or ECU whatever they call it on your year. I’ll be home this weekend and I’ll check it out and tell you the dealio. My Z doesn’t have T-tops and you said it was a buzzing sound you heard? My seems more like a metallic click like possibly a relay but I’m not sure what it is because I haven’t pulled off the panel to see if the noise is actually issuing from there. I drove it about 300 miles before it shut down just like old times last weekend. Other than a slight miss in the timing, it didn't give me any problems so I hoped and wished that I fixed it. I didn't drive it all this summer and I got it back from the shop about three weeks ago from getting the new timing belt and distributor installed. Wow, I thought I was the only one on earth and my Z was cursed! Anyway, now that you mention it, my car seems to fail more frequently in the summer too. I recently put in a new timing belt and distributor but the problem persists, it will start fine most of the time and at random intervals it will just shut down. I took it back to the dealership and they said that the distributor had weak resistance and the timing belt was loose. I checked the relays, fuses, and fusible links but found nothing. I had a mechanic put in a new ignition switch and some fuel components to see if that pacified it but it didn't. After that the frequency increased so I took it to the dealership and they said they couldn't find anything wrong. It did this at intervals of about two weeks three times after that, always at the same distance from the house.
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I came back after school and it started and ran rough for a bit but then ran normal.
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About a year ago I was driving to school in the morning and about 1.5 miles from my house my car died, no sputtering, nothing, it completely shut off and wouldn't start it would crank over but not even try to start. I have had a 1984 300ZX non-turbo for 2.5 years and have been having problems lately and now it has become so bad that I can't drive it.