cheekychimp
Well-known member
I recently picked up a bone stock 1990 RHD JDM VR4 from Japan.
The car is in excellent shape but when I first looked at it (several months back), it was throwing an intermittent CEL. After a short drive the CEL disappeared and whilst all the documentation for the car was going through the importer supposedly had a garage check this out. Now I have no reason not to believe he did this but I suppose you can never really be sure unless you do something yourself, but anyway he came back and told me they'd plugged in a diagnostic computer and the car wasn't throwing any codes.
So fast forward to about a week or so ago and after I picked up the car it would do the same thing. Drives perfectly, exhibits no signs of any problems whatever. Pulls strong (well as strong as it can on the stock 7 psi or whatever) no break ups, idles smooth but when cold it throws a CEL light usually on deceleration as you push the clutch in coming up to a junction. On more than one occasion it has flashed a number of the warning lights for brakes (ABS), oil and CEL.
Dan (sixsixtwo) is in town at the moment and has been out in the car a few times. He mentioned something about how a faulty alternator can cause the CEL and brake (I presume ABS again?) idiot lights to come on. I became a bit suspicious at this stage as the car usually started straight up but occasionally wouldn't turn over and struggled to start as if the battery was very low. Last night after pigging out at TGI Fridays, I could see the dash lights starting to dim on the way home. It was night, we had the headlights on, the AC was on full power and we were doing a lot of stop and go driving, with four people in the car. As soon as I dropped Dan off and hit the highway, things seemed better.
This morning I tried to start the car and the battery was pretty much dead. It really didn't sound as if it would start but suddenly it turned over and fired. As soon as it started it ran fine. I'm leaning towards the battery not holding a charge. If I start the car and disconnect the battery and it still runs is that any indication of the alternator serviceability or do I need to get a multimeter on it to be sure? I have a good alternator I can swap in but I didn't really want to be doing that this weekend. One other thing I noticed was a low pitched whine coming from behind the radio bezel area. Is the MPI relay in there? It was not a clicking sound, definitely a whine but that is the only other thing I can think of in that area linked to these particular symptoms.
I think I will change the battery regardless but I think I should confirm the charging system is healthy or I'm just going to be masking the issue for a few more days until the new larger battery runs down. Anything else I am missing or should be checking? Battery terminal connections? Specific Grounds etc?
The car is in excellent shape but when I first looked at it (several months back), it was throwing an intermittent CEL. After a short drive the CEL disappeared and whilst all the documentation for the car was going through the importer supposedly had a garage check this out. Now I have no reason not to believe he did this but I suppose you can never really be sure unless you do something yourself, but anyway he came back and told me they'd plugged in a diagnostic computer and the car wasn't throwing any codes.
So fast forward to about a week or so ago and after I picked up the car it would do the same thing. Drives perfectly, exhibits no signs of any problems whatever. Pulls strong (well as strong as it can on the stock 7 psi or whatever) no break ups, idles smooth but when cold it throws a CEL light usually on deceleration as you push the clutch in coming up to a junction. On more than one occasion it has flashed a number of the warning lights for brakes (ABS), oil and CEL.
Dan (sixsixtwo) is in town at the moment and has been out in the car a few times. He mentioned something about how a faulty alternator can cause the CEL and brake (I presume ABS again?) idiot lights to come on. I became a bit suspicious at this stage as the car usually started straight up but occasionally wouldn't turn over and struggled to start as if the battery was very low. Last night after pigging out at TGI Fridays, I could see the dash lights starting to dim on the way home. It was night, we had the headlights on, the AC was on full power and we were doing a lot of stop and go driving, with four people in the car. As soon as I dropped Dan off and hit the highway, things seemed better.
This morning I tried to start the car and the battery was pretty much dead. It really didn't sound as if it would start but suddenly it turned over and fired. As soon as it started it ran fine. I'm leaning towards the battery not holding a charge. If I start the car and disconnect the battery and it still runs is that any indication of the alternator serviceability or do I need to get a multimeter on it to be sure? I have a good alternator I can swap in but I didn't really want to be doing that this weekend. One other thing I noticed was a low pitched whine coming from behind the radio bezel area. Is the MPI relay in there? It was not a clicking sound, definitely a whine but that is the only other thing I can think of in that area linked to these particular symptoms.
I think I will change the battery regardless but I think I should confirm the charging system is healthy or I'm just going to be masking the issue for a few more days until the new larger battery runs down. Anything else I am missing or should be checking? Battery terminal connections? Specific Grounds etc?
Last edited:
