Previous owner of the car did some soldering in the ecu when he manual swapped the car what I am wondering is because I believe it to be bad is do I need to replace with a automatic ecu or can I replace it with a manual so I don’t have to solder anything

 

if its currently a manual use a manual ecu

 

okay so I replaced the ecu car fired up and ran shut it off and now all it does is turn over what could be the issue

 

Okay so here’s the deal bought the car previous owner manual swapped the car soldered the ecu, that ecu went bad swapped it with a manual ecu car fired and ran perfectly shut the car off and now all it does is turn over I’m stumped on what it could be if anyone could help thanks

car is a race car (completely stock) motor and trans no mods what so ever so how ever I can get this to work would be great

ps if I swap back to the old ecu the car will fire up and run because there was fuel sent by the new one but won’t STAY running for long because it’s not sending power to the main relay but as soon as I switch to the new ecu the car will fire and run great but as soon as i shut it off I’m dead in the water again

 

FYI: The ECU does not send power to the main relay.

Do some basic no-start diagnostics. Then go from there.

 

Two threads on same topic.

 

I have.... that’s why I’m here

and from everything I’ve read on hear and people I’ve talked to on hear all seem to say it does and the main relay wasn’t working with the bad ecu and when I changed for the new one it is so how does that work?? How else would it get power??

 

yeah sorry made another more in depth one because I wasn’t getting help here

 

Either way that’s all besides the point and far from what I asked about

yeah it may sounds stupid but the only way i can get the car to run is by swapping back and forth the 2 ecu’s I don’t know how that makes any since because I know one for sure is bad and I’ve tried everything So I’m at a lost to why the car will not run when everything seems to be in working order and why once I finally get it running it runs and drives as should but soon as I shut it off will not start back up so any help on that would be appreciated... thanks

 

If you have done basic no-start diagnostics, then post the details.

They are wrong. Don't believe everything you read on the internet.

Haha...all electric circuits require both power and ground. The ECU does not supply voltage ("power") to the main relay but it does supply ______________ to the main relay.

I'll let you fill in the blank.

 

I'm trying to help you because...you need help. You can either listen to good advice or discard it. It's up to you.

 

okay well my bad for getting it wrong...

either way this is still not fixing my issue or issues I’m having

it’s getting fuel
has spark
and plenty of air

it tries to run but isn’t that’s why I’m at a lost because if it has all of those it should be running no issues but as I said once I fight it for hours I’ll get it running and it runs and drives great like it should but I shut it off and try to start it immediately after it just turns over and some other guy I’ve talked to said “maybe” it needs a base line tune that the ecu isn’t communicating properly but I’m not a Honda guy by no means bought the car because it was cheap and ran great when I got it a couple months ago nothing has change but the car being gutted and roll cage (no I didn’t cut wires or anything out)

 

I mean I don’t really see that I could just be reading you wrong but anything to get me up and rolling again would be great so if you can help that would be much appreciated

 

Details on fuel and spark?

What specific tests were done and what were the results?

Other important basic no-start diagnostics:

The engine also needs - (1) compression and (2) proper mechanical timing.

 

well it was done the incorrect way because I’m limited on tools so I cracked open a fuel line before the injectors and fuel pumped out while pump was running

spark was done the same way with a screwdriver in the spark plug wires (shocked the **** out of myself multiple times)

and did not do a compression test and the car ran perfectly before the ecu went bad and the only way I know that it is bad is because I opened it and there is a lot of melted parts inside and arc marks on the lid of it so I think compression and timing are fine also like I said it’s a race car and was at the track last weekend and ran flawlessly

 

Don't make assumptions. You need to cross items off the list of basic no-start diagnostics.

 

okay I’ll try again in the morning when I have daylight what is a good way to test the injections like I said I’m limited on tools and don’t have very many ways of testing things I also tired the starting fluid it does nothing like it’s not getting fuel but it is at least to the injectors but I don’t know if it is from them and I had it running today that’s why I said I’m at a lost because it works then doesn’t

 

Repeating that you're lost doesn't help, but telling us results of ALL no-start diagnostic tests does help.

If you are saying that spraying starting fluid into the throttle body does not keep the engine running, then you don't have a fuel problem.

You could have weak spark or the firing order of the plug wires is wrong, but first check the mechanical timing.

If the timing is fine, compression test the cylinders.

 

yes spraying starter fluid into the throttle body’s does not keep the car running

and as for plug wire or firing order being wrong it ran perfectly fine last weekend at the track with the old ecu and today when I put the new ecu in , I drive the car for maybe 45 mins and shut it off and immediately tried to restart it as I was having issues with the main relay to see if it fixed the problem and it would not restart and hasn’t since so I don’t know how the timing or firing order would’ve change the plugs and wires and newer

could the ecu call for a different firing order?

if so why or how if it is for the d15b7 motor and the 95 dx just the manual ecu?

 

 

I’ll give it all a shot in the morning and get back with you thanks 👍🏻

 

Ask a MOD to merge the two threads... this places all of the responses for you, and those who search this topic in the future, in one place instead of two.

 

Is the check engine light on?

 

no check engine light

 

how would I test for weak spark firing order is right and timing is just a smidge advanced I have no means of compression testing