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Daniel Wilson
Daniel Wilson,
Category: Honda
Satisfied Customers: 4398
Experience:  Owner at DJ Wilson
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I've replaced main relay. Checked fuses and grounds. Have

Customer Question

I've replaced main relay. Checked fuses and grounds. Have new fuel pump and distributor. That includes new ignitor and coil . I have no spark . no injector pulse. So I swapped ECU's with a known good one. I still have no fire or no pulse. I hit 1 to seven and my fuel pump kicks on. I hit 1 to 5 and my fuel rail pulses. My tps has no voltage as well. Will this cause my no spark no fuel issue?
Submitted: 8 months ago.
Category: Honda
Expert:  Matt C. replied 8 months ago.
Hello, I would like to see if I could help you figure this out. What year, model, and engine size is this vehicle?
Customer: replied 8 months ago.
It's a 1991 Honda accord. I got it a couple months back. I replaced alot on it already . has new header, 02 sensor. Starter, fuel pump, fuel pump relay, ECU, plugs wires, and whole distributor assembly. I shut the car off one day and came back out and it wouldn't fire. Then I noticed fuel pump wasn't kicking on. Replaced fuel pump.p, relay, and nothing , I then put another distributor on it and it fired right up. That lasted a week and then did the same thing. So then I got an all new distributor thinking that one went bad and still nothing. So I replaced ignition switch. Couple sensors on side of block. Flipped around a couple main relays but all do the same thing. When I jump the wires I hear fuel pump coming on. I also have power to the ignitor. Coil is good . the check engine light stays on the whole time so I can't pull any codes. I checked throttle body sensor and I have no power on the harness. But when I run 12 v to it it makes the fuel rail hum I think. Something on top of motor is making noise. Any help or ideas will help out alot
Expert:  Matt C. replied 8 months ago.
OK, I see you have replaced a whole lot of components, have you actually tested anything or have you just been throwing parts at it?Secondly, do NOT apply 12v to the TPS again, that sensor runs off of 5v. Applying 12v to a 5v circuit can cause sensor and computer damage.
Customer: replied 8 months ago.
Okay I understand about the 12 volt ordeal with the tps. Yes I have a volt meter and a test light using for these test. And I know it runs off five volts. I test it first to see if the harness was getting any juice . I used a 12 volt battery that's pretty low on volts trying to see if I could get a signal from it. And I did. Now I have tested the coil. The ignitor. Now without sending a signal to the tps I do not get a pulse from neg off the coil. But I have three ignitors that I have swapped two used and one brand new. The 13 volt input on the ignitor has power. The coil has power. The main relay has power. I redid the ground 101 under thermostat housing. I also swapped out the ignition switch. I've checked most of the sensors on the block. I doubt one that was cracked in half under distributor. Replaced it and didn't change anything . I was hoping this was an easy fix that I was just missing something small. I have full header and exhaust. New o2 sensor ad well. Sending unit and fuel pump both new and have power. But now that it's not running the fuel pump don't prime the injectors. My relay only kicks on one click. My cell stays on constant. Can't pull any codes. Both ECU's look fine no damage. I'm clueless. I don't mind having new parts because I'm keeping this carbfor awhile. Has rebuilt tranny. New timing belt. Motor cranks strong. Good compression. When it runs it doesn't leak any fluids and it runs strong. I know this is something a Honda guy will need to solve beings this is my first Honda I've done this much work on.
Expert:  Matt C. replied 8 months ago.
OK, so if I am understanding you correctly, you had an intermittent no start prior. Now it will not start at all.Have you checked the spark plugs to see if they are firing? If the spark plugs are firing then I would like to verify this is a fuel problem by spraying a little starting fluid into the intake and trying to start it and see if it fires up.
Expert:  Matt C. replied 8 months ago.
I am going to need you to do that so I can narrow down the possibilities, then we can work from there.
Customer: replied 8 months ago.
No spark at the coil and no fuel.
Customer: replied 8 months ago.
That was the first thing I checked. Main relay clicks once but does not do the initial second click or the third click. AMD since we have baught the car it was always slow at starting until it got warm. Once i drove it and it warmed up it had no issue starting. Then one day ibdrove it and shut it off at gas station. Came out five minutes later and no spark and no fuel. Put a used distributor on it and it fired up. RAn for about a week and now it's doing same thing. A new distributor did not work this time around. I can jump the harness at main relay and fuel pump primes. I don't notice anything when I jump 1 to 5 though.
Customer: replied 8 months ago.
And if I'm not getting any power at the tps what would cause that
Expert:  Matt C. replied 8 months ago.
It sounds very much like you still have either an issue with the main relay or the harness. Everything you have described are all classic symptoms of it. The TPS is likely not getting power because that relay is not staying energized.Here is what I would like you to do: 1. Verify again all fuses are good.2. Check for the following at the main relay, with it connected.Yel/blue should have +12 volts battery, always.Blk should be grounded always. Connect your negative voltmeter or DMM lead here.Blk/yel should have +12 volts with ignition ON.Not used. Yel/blk should be +12 volts with ignition ON.Blu/Red (auto only) Blk/grn (manual only) should be +12 volts at START.Yellow should have +12 volts temporary with ignition ON, if idling or start Yellow should have +12 volts.Grn/blk should ground temporary with ignition ON or idling, if idling or start Grn/blk should ground.
Customer: replied 8 months ago.
Okay I checked all wires. I have 12 v to all of them except the yellow wire. Even when I try to start I have nothing.
Customer: replied 8 months ago.
Can I just run a 12 volt wire to it ?
Customer: replied 8 months ago.
Even if I have to hook it up on a switch to kill the car would that work? Or run it off my fuse box accessories
Expert:  Matt C. replied 8 months ago.
If there is power on the blk/yellow wire, and there is ground on the green/blk and you still don't ever see power on the yellow wire, it sounds like you have a faulty main relay. I do not advise in running a 12v source directly to it, to do that you would have to wire in a relay so you can have the switch on the ground side of the circuit to prevent the switch from burning up.
Customer: replied 8 months ago.
My light came on 1,3,5 but not seven.
Expert:  Matt C. replied 8 months ago.
Terminal 7 comes from fuse #28 in the under hood fuse box. Remove and inspect the fuse and make sure the terminals in the fuse box for that fuse look good.
Customer: replied 8 months ago.
#28 was good. I also checked the yellow and green wife off my harness to the distributor and I have no power going to it. I'm going to use my meter and double check for any volts. I'll try to crank the engine over to see if I ha e any volts jumping if I do have any.
Customer: replied 8 months ago.
The coil has power though. But I think indont have any power going to ecm. I'm checking now
Customer: replied 8 months ago.
Okay I checked voltage at yellow and green wire at distributer. I have 12 volts but I have no pulse. What does this mean. What should I check next ? I'm going to swap out ignitors again and see if I can get any diff readings. But what do you think.?
Expert:  Matt C. replied 8 months ago.
I honestly would say you should try getting another main relay. From the results you gave me from testing the harness at the relay, it is telling me that the relay is faulty and you should replace it before doing anything else.
Customer: replied 8 months ago.
Okay I'll try that
Customer: replied 8 months ago.
Ordered one. So I'll let ya know when it comes in and if my issues are still there.
Expert:  Matt C. replied 7 months ago.
Hello, I just wanted to follow up with you and see if you got everything sorted out.
Customer: replied 7 months ago.
Tried a new main relay . same issue. I can't get any spark. Fuel pump still won't prime
Customer: replied 7 months ago.
I tried my test light at the harness with key in the on position. I have nothing lighting up when I run it off a body ground. My wires look good. My grounds are good. I was hoping to find a faulty wire somewhere but I can't see anything wrong with them. Hi know that have a good fuel pump. A good distributor. Ignitors,coil, control mod
Customer: replied 7 months ago.
And I meant the harness at the distributor.
Expert:  Matt C. replied 7 months ago.
I am going to opt out and give some other experts an opportunity to see if they can help you a little further.
Customer: replied 7 months ago.
Okay well to whom it may concern . I have replaced with new a new control module,a while new distributor , plugs wires, fuel pump ECU. Ignition. Switch. O2 sensor. . the main relay. my car was running. Broke down. I switched distributor and ran another week. Now broke down and a new distributor didn't fix the problem. So all parts replaced are after it broke down this time. I have checked all my grounds . if I jump the harness at the main relay 1 to 3 3 to 5 and 5 to 7 the fuel pump kicks on bit still no spark. All fuses are good. What else can I check.
Customer: replied 7 months ago.
The only issues with the main relay it seems as 7 and 8 . when I crank to start 7 isn't getting 12 volts.
Customer: replied 7 months ago.
If I ground 8 fuel pump kicks on. If I put 12 volts to seven fuel pump kicks on. But I still have no spark. What's up with this scenario
Expert:  Daniel Wilson replied 7 months ago.
Hi my name is ***** ***** the ECU is new then the likely cause of no fuel or spark is the loss of engine speed signal to the ECU. Check the crank/cam sensor and harness for problems and let me know the results
Expert:  Daniel Wilson replied 7 months ago.
Hi, Did you get this resolved?
Customer: replied 7 months ago.
The crank sensor I'm the distributor? It's a new distributor . I've tried swapping out another used one as well and still same results. I have power everywhere but it's not sending a pulse . no spark to the coil. And fuel pump doesn't prime. Relays good. Fuses are good. Ecu is good. Check engine light is solid all the time so no difference on the light. Just stays on. I can't diagnose this issue
Expert:  Daniel Wilson replied 7 months ago.
The crank sensor is only one possible cause. Other causes of no spark are faulty coil, cap and rotor, distributor, timing belt failure, Low compression, low fuel pressure, etc. click on this link as it is a great troubleshooting tool to use. follow the flow charts and links to test the different components listed above to isolate the cause. Let me knowTroubleshooting