CRX no start diagnosis help

My dad is the original owner of a 90 CRX HF. He drives it very little; the car has just over 50,000 miles on it. He's always had it maintained at the local Honda dealer according to schedule--it's a very well-kept car. He recently told me that on occasion, the car won't crank, acting as if it has a dead battery. Through trial and error he found that manipulating the throttle body by hand seemed to unstick something, as the car starts every time after he does that.

I've tried to help him with it, but he lives in CA and I live in TN, so all I can do is make guesses about what he tells me over the phone or via email. He's also not very knowledgeable about this sort of thing. I told him how to clean the throttle body, thinking something might be causing it to stick. That didn't solve the problem. I have no idea why anything related to the throttle body would cause the starter not to crank, but I don't have much Honda experience. Does anyone have an idea what would cause such a thing?

very typical of CRX's is the main fuel pump relay going "bad" .... not bad so much as the solder joints just need re-flowing .... a bear to get to, and even harder to put back.... you know the drill ... lying on your back, head on the pedals, working more by feel than sight .... trying to line up the bolts... I ended up just zip tying mine in the space where the coin tray used to be

have never had a starting problem since then... might not be your Dad's problem but it's one I'd go ahead and take care of .... he'll have to sooner or later no matter what else you find

mine would start then die... start again , die again.... several times ... then fire up and go.... that might not be the only symptom .. you're Dad's could be another leading to the same solution

That doesn't sound like a main relay to me. The main relay starts the fuel pump so it would crank and crank and crank but wouldn't start until the check engine light turned off. I too did the ziptie trick.

It's probably not a bad idea to swap it out or have one around for when you do need it but I don't think that's the problem. I don't know what it would be either.

Next thing to check is the clutch interlock switch. There's a plastic button that rots out that if not in place will prevent the switch from engaging. Look also for little bits of the button in the drivers floorboards.

Bad ground? The main ground terminal to the battery doesn't really fit aftermarket batteries well, and there is only one other ground strap to the motor. Make sure the grounds are all tight, and perhaps even add an extra.

frenchy wrote: That doesn't sound like a main relay to me. The main relay starts the fuel pump so it would crank and crank and crank but wouldn't start until the check engine light turned off. I too did the ziptie trick. It's probably not a bad idea to swap it out or have one around for when you do need it but I don't think that's the problem. I don't know what it would be either.

really no need to swap it out... just get some liquid solder flux and reflow each connection that you can see...

the fuel pump relay problem manifests itself in a variety of ways... mine would crank and crank and crank... then catch .... then die .... over and over and over ... then finally would stay running and not be a problem as long as I didn't shut it off... even then about 60% of the time it would start right up when next I tried

you should probably just throw in the towel and sell that original-owner, absurdly low mileage CRX HF to me.

wbjones wrote: the fuel pump relay problem manifests itself in a variety of ways... mine would crank and crank and crank... then catch .... then die .... over and over and over ... then finally would stay running and not be a problem as long as I didn't shut it off... even then about 60% of the time it would start right up when next I tried

^This.......

My '90 Civic (same engine with DPFI) had a bad fuel pump relay. I couldn't diagnose it, a Honda-specific shop couldn't diagnose until it died. The bad part was that it died half a mile after the shop said they couldn't find the problem until the car was "dead".

The FP relay went totally south a couple days later and replaced; everything's been fine since.

The problem here, though, is that when this happens, the car won't crank at all until he fiddles with the TB. Which, unless Hondas are THAT much different from the domestic stuff I'm used to, shouldn't affect the electrical system in any way.

And EVERY time he fiddles with the TB it starts when he gets back in the car. That fixes the symptom, but obviously not the disease.

Will wrote: The problem here, though, is that when this happens, the car won't crank at all until he fiddles with the TB. Which, unless Hondas are THAT much different from the domestic stuff I'm used to, shouldn't affect the electrical system in any way. And EVERY time he fiddles with the TB it starts when he gets back in the car. That fixes the symptom, but obviously not the disease.

There is nothing about fiddling with the TB that should fix a non-starting issue.

My gut feeling is that opening/slamming the hood is jarring the main relay enough to make contact and function until it doesn't again. The fact that it is right above the hood pop handle might be part of this.

DILYSI Dave wrote: There is nothing about fiddling with the TB that should fix a non-starting issue. My gut feeling is that opening/slamming the hood is jarring the main relay enough to make contact and function until it doesn't again. The fact that it is right above the hood pop handle might be part of this.

I suggested my dad try just opening and closing the hood as you said to test your hunch. Today he said the car didn't start. He opened the hood, then dropped it. The car wouldn't start. He opened the hood again, manipulated the TB, dropped the hood, and the car started.

I agree that manipulating the TB shouldn't affect a no-start condition, but it fixes the symptom (if not the problem) 100% of the time. I'm not sure what to make of this.

UPDATE: I just spoke to my dad, and he said this time the car cranked, but wouldn't start. That sounds more like the fuel pump situation people mentioned.

the fuel pump problem is so common that that's the first thing anyone mentions when there is a fuel related problem with a CRX... might not be the solution for your Dad but it's still something I'd pull and re-solder .... eliminate the most common and go from there ( keep in mind that you usually can't see anything wrong with the solder joints .... just reflow them and see what happens )

let us know how it goes for him

That's definitely not a repair he can handle, and I probably won't be back out there until Christmas. If it's as hard to get to as people have said, what would a shop charge him to fix it?

Maybe one of our guys who lives in CA could take a look at it for you? Be cheaper than a shop.

I would assume it'd be 2 hours of shop time give or take, plus the relay. Probably be into the repair for $200 +/- if I had to guess.

It's 2 bolts ( I think ) and an electrical clip.... a few screws ( don't remember 2 / 3 / 4) solder paste / flux and reflow the existing solder ... odds are no need to buy a new one