GSL-SE won't start - HELP PLEASE
08-21-17, 06:58 PM
#1
Full Member
Thread Starter
GSL-SE won't start - HELP PLEASE
Hello again,
I've been having an issue with this car since I bought it from a local dealer here in Lafayette, CO. The car appears to have a weak spark. It revs and is about to start, but it doesn't catch on the first spark. On subsequent start it won't even try to catch. So frustrating. The plugs were all wet after reving it for 20-30 sec. I start the car without pressing on the gas pedal, but with clucts depressed or not, no difference.
So far I replaced:
distributer cap and rotor,
plugs, wires,
coils tested and are good,
igniters are good (quite sure),
new fuel pump (it had the original pump from 1984),
injectors tested out of the car and were spraying fine.
new injectors harness, because the old injector harness connectors were holding on a piece of wire!
Haven't tested the ECU and the distributor pick up coils. Just about everything else has been tested more or less. The distributor is original, was never out of the car. The ECU gives the pulse to the injectors, otherwise the plugs wouldn't get wet, but I haven't tested the ECU.
I was told the car has excellent strong 13B engine and I really really want to get it running. No RX7 mechanics in Lafayette, very frustrating.
Please help!!!!
I've been having an issue with this car since I bought it from a local dealer here in Lafayette, CO. The car appears to have a weak spark. It revs and is about to start, but it doesn't catch on the first spark. On subsequent start it won't even try to catch. So frustrating. The plugs were all wet after reving it for 20-30 sec. I start the car without pressing on the gas pedal, but with clucts depressed or not, no difference.
So far I replaced:
distributer cap and rotor,
plugs, wires,
coils tested and are good,
igniters are good (quite sure),
new fuel pump (it had the original pump from 1984),
injectors tested out of the car and were spraying fine.
new injectors harness, because the old injector harness connectors were holding on a piece of wire!
Haven't tested the ECU and the distributor pick up coils. Just about everything else has been tested more or less. The distributor is original, was never out of the car. The ECU gives the pulse to the injectors, otherwise the plugs wouldn't get wet, but I haven't tested the ECU.
I was told the car has excellent strong 13B engine and I really really want to get it running. No RX7 mechanics in Lafayette, very frustrating.
Please help!!!!
08-23-17, 05:40 AM
#3
Are you getting tach movement when cranking? Also, are you positive you are getting good spark? Have you ran a compression test on the engine yet? I would do that asap. Have you tested the mass airflow meter's resistance values per the fsm? These are the places that I would start.
08-23-17, 12:44 PM
#4
Full Member
Thread Starter
Are you getting tach movement when cranking? - YES
Also, are you positive you are getting good spark? - NO see above my first message, I think I have a weak spark. I can upload a video of the sparks on all plugs. It should be a nice blue spark mine is orange.
Have you ran a compression test on the engine yet? - NO why? And how do you do a compression test on a rotary engine?
I would do that asap.
Have you tested the mass airflow meter's resistance values per the fsm? NO - again why is this relevant?
These are the places that I would start.
Also, are you positive you are getting good spark? - NO see above my first message, I think I have a weak spark. I can upload a video of the sparks on all plugs. It should be a nice blue spark mine is orange.
Have you ran a compression test on the engine yet? - NO why? And how do you do a compression test on a rotary engine?
I would do that asap.
Have you tested the mass airflow meter's resistance values per the fsm? NO - again why is this relevant?
These are the places that I would start.
08-24-17, 05:46 AM
#5
As far as the spark goes, and in reference to the coils, I would replace the coils. They can spec out ok on a multimeter and still be faulty. I had this happen two summers back on my 85 GS that I installed an SE engine into. The engine would break up and the plugs were fouling and I checked everything and by chance tossed some good known coils on the car and low and behold, its been running perfectly ever since. I learned the hard way on that one and it took me a week to figure out the issue.
I've never seen a distributor fail in 19 years of owning and working on 7's. The N304 ecu rarely fails. The only one I've seen fail was submerged from a flood. And the car was still running. Not saying that it wouldn't fail, its just not a common failure point.
It can't hurt to test the MAF. It can cause wonky fuel delivery issues and odd running issues. Not related to spark of course but something to look at as far as overall diagnostics is concerned. I've seen them fail and give some pretty wild resistance numbers across the range and cause nasty issues of random no starts and such.
To test the compression, a rotary compression tester would be the best choice. You can however get a good idea with a piston compression tester. Low compression can cause flooding issues and of course wet spark plugs. The weak ignition makes me think that compression is good simply because you said the engine will run with the weak spark. But compression is good to check to rule it out as a possible suspect with any diagnostic inspection. I bought a rotary compression tester and it has helped me immensely.
I've never seen a distributor fail in 19 years of owning and working on 7's. The N304 ecu rarely fails. The only one I've seen fail was submerged from a flood. And the car was still running. Not saying that it wouldn't fail, its just not a common failure point.
It can't hurt to test the MAF. It can cause wonky fuel delivery issues and odd running issues. Not related to spark of course but something to look at as far as overall diagnostics is concerned. I've seen them fail and give some pretty wild resistance numbers across the range and cause nasty issues of random no starts and such.
To test the compression, a rotary compression tester would be the best choice. You can however get a good idea with a piston compression tester. Low compression can cause flooding issues and of course wet spark plugs. The weak ignition makes me think that compression is good simply because you said the engine will run with the weak spark. But compression is good to check to rule it out as a possible suspect with any diagnostic inspection. I bought a rotary compression tester and it has helped me immensely.
08-24-17, 01:35 PM
#6
Full Member
Thread Starter
As far as the spark goes, and in reference to the coils, I would replace the coils. They can spec out ok on a multimeter and still be faulty. I had this happen two summers back on my 85 GS that I installed an SE engine into. The engine would break up and the plugs were fouling and I checked everything and by chance tossed some good known coils on the car and low and behold, its been running perfectly ever since. I learned the hard way on that one and it took me a week to figure out the issue.
I've never seen a distributor fail in 19 years of owning and working on 7's. The N304 ecu rarely fails. The only one I've seen fail was submerged from a flood. And the car was still running. Not saying that it wouldn't fail, its just not a common failure point.
It can't hurt to test the MAF. It can cause wonky fuel delivery issues and odd running issues. Not related to spark of course but something to look at as far as overall diagnostics is concerned. I've seen them fail and give some pretty wild resistance numbers across the range and cause nasty issues of random no starts and such.
To test the compression, a rotary compression tester would be the best choice. You can however get a good idea with a piston compression tester. Low compression can cause flooding issues and of course wet spark plugs. The weak ignition makes me think that compression is good simply because you said the engine will run with the weak spark. But compression is good to check to rule it out as a possible suspect with any diagnostic inspection. I bought a rotary compression tester and it has helped me immensely.
I've never seen a distributor fail in 19 years of owning and working on 7's. The N304 ecu rarely fails. The only one I've seen fail was submerged from a flood. And the car was still running. Not saying that it wouldn't fail, its just not a common failure point.
It can't hurt to test the MAF. It can cause wonky fuel delivery issues and odd running issues. Not related to spark of course but something to look at as far as overall diagnostics is concerned. I've seen them fail and give some pretty wild resistance numbers across the range and cause nasty issues of random no starts and such.
To test the compression, a rotary compression tester would be the best choice. You can however get a good idea with a piston compression tester. Low compression can cause flooding issues and of course wet spark plugs. The weak ignition makes me think that compression is good simply because you said the engine will run with the weak spark. But compression is good to check to rule it out as a possible suspect with any diagnostic inspection. I bought a rotary compression tester and it has helped me immensely.