Ign. Coil - affect on Fuel Pump ?

[Lester Lugnut]

87 Accord Lx - carb - automatic.

Car won't start - when turning ign. switch, engine ocassionally bucks, but wont' start. Battery charged up. I pulled fuel line from behind secondary filter(under the hood) and cranked. No fuel, so I suspected fuel pump or fuel cutoff relay.

I used the silver factory service manual and ran diagnostics on the fuel cutoff relay. Jumpering pins 1 & 2 should have caused fuel to flow. It did not, so I replaced fuel cutoff relay as instructed.

Problem continues after changing fuel cutoff relay. Crank engine repeatedly and you get an occasional buck from the engine.

I seem to recall reading the the ign. coil provides power to the fuel pump. If that's so, I may have a bad coil vs. a bad fuel pump?

Could someone verify this?

Thanks.

[Hondaisok]

My guess by reading the service manual is either your pump is bad, or a fuel line or filter is clogged.

[joebeets]

Your ign. signal goes to the FP relay to activate it. Once activated, power is sent to pump. You need to check for voltage at the pump, accessible via the trunk.

[joebeets]

I used the silver factory service manual and ran diagnostics on the fuel cutoff relay. Jumpering pins 1 & 2 should have caused fuel to flow. It did not, so I replaced fuel cutoff relay as instructed.

Are you sure those were the instructions? Logically that implicates the pump, not the relay.

[lostforawhile]

yea you've got that backwards big time, if you jumper those pins and the pump doesn't run the pump is bad. the fuel pump relay detects the pulses from the igniter unit in the distributor,any time the engine quits turning,those pulses stop and your pump shuts off,eg. you get in a wreck,the engine quits on impact,the pump turns off to keep you from being roasted in a gasoline fire. also if you break a fuel line,the engine stops so does the pump. put the relay back in that you thought was bad, unplug the pump and check for continuity across the two terminals on the pump. more then likely the motor burned out on the pump. if that doesn't help jumper the two wires at the relay,then check for voltage at the pump electrical plug with the key on. if you have voltage or the pump has no continiuity you need a pump. if you pull an old relay at the junkyard,just open it up and solder a couple of wires across those two terminals,then you can plug it in and connect the two wires,so much easier then trying to reach them under the dash.

[Lester Lugnut]

First off - thanks for the replies. I'll quote page 11-45 of my factory '87 Accord manual.

Step 6

turn ign. off

connect a jumper wire between #1 terminal and #2 terminal.


Step 7

turn ign. switch on.

the fuel pump should run

if the fuel pump does not run, check yellow wire between fuel pump & fuel cutoff relay & check black wire from the fuel pump to ground.

if the wires are ok, replace the fuel cut-off relay & retest.

************************************************** *******

ok - jumpering 1 & 2 did not flow fuel. i suppose as stated in the 1st reply that the primary or secondary filter could be plugged, but those were changed about 3 months ago. i realize tank sediment could have plugged the rear filter, especially in a car this old.

if i understand previous posts here correctly, the pump should run for a few secs. when the ign. switch is turned to 1st position. i'll pull the trunk carpet, put a mechanics stethescope on the pump and have someone turn the key to the 1st position to see if the pump is even priming.

[lostforawhile]

there is a serious misprint there,when you jumper those wires,you are sending voltage directly to the pump, that takes the fuel pump relay out of the equasion,if the pump doesn't run with the relay bypassed why would you replace the relay? it's not doing anything with it bypassed,read that again,it should say with the relay bypassed if the pump [COLOR="black"]runs!!R]then bypass the relay,trust me i know all about the electrical system in this car,i've done this

[lostforawhile]

oh you are misreading that,they are saying if the pump doesn't run,put the relay back in and retest,not replace the relay. what kind of car do you have anyway,do you have an acess hole for the pump? or is yours one of the cars where you need to pull the tank,

[A20A1]

Holy shiz, joebeets. Haven't seen you post in a while.

[Lester Lugnut]

oh you are misreading that,they are saying if the pump doesn't run,put the relay back in and retest,not replace the relay

I quoted the manual word for word - go back and read the end again - it says "replace".

However....I agree with what you and Joe said - if the pins are jumpered, the device should be bypassed and power sent directly to the pump. I believe the text is incorrect.

As I said earlier, I'll have someone turn the ign. switch to the 1st pos. while I hold a mechanics stethescope on top of the pump cover and listen for the 2 sec. priming. If it's priming, I'll replace all filters again and check the fuel line for clogging. If I don't hear that, I'll test for volt. at the connection on the pump. If I'm getting volt. at the connection, I'll replace the pump.

Will update this post when I get it running.

Thanks for all of the input. This is a good site.

[lostforawhile]

I know what it says,I read it,when a honda manual says replace in that context it means you have taken the part out now put it back in. if you bypass the relay and the pump doesn't run the relay is already out of the loop. if the relay was bad the pump would have run. it's just a switch,if you flipped a switch in your house and a light didn't come on,and then you bypassed the switch,and it still didn't come on,you wouldn't replace the switch,you would replace the light bulb. hope that example helps. change the text to if the pump doesn't run put the relay back in and retest. thats what they are saying. try this,connect a small 12 bulb to the two terminals that go to the pump at the pump,turn the key on and crank the car,the bulb should light up for a second. how that works is when the relay first detects ignition voltage it allows the pump to run for a couple of seconds,to make sure there is fuel in the line and the fuel bowl.

[joebeets]

Holy shiz, joebeets. Haven't seen you post in a while.

Thanks A. Quality vs. quantity, fo' shizzle.

[Lester Lugnut]

Fuel pump works - getting fuel to the other side of the secondary fuel filter outlet - all the way to the carb.

Pulled #3 spark plug - very wet.

Tested ign. coil - flunked 2 of the resistance tests, but marginally. Not convinced it's bad.

Will next pursue diagnosing the igniter. Maybe tomorrow.

[lostforawhile]

now i got lost here somewhere,is it just not starting or quiting after running,watch that coil,I had one like that, it would barely pass the reisitance tst,but when it got hot soaked from engine heat it would fail. put a junkyard one in has been fine ever since.

[Lester Lugnut]

The car is not starting. Testing "cold" ignition parts..ie..coil, igniter.

Ambient temp about 70F at mid-day.

One of the resistance tests for the coil showed a range of 1.2 - 1.5 ohms. Mine read 1.7. Another resistance test indicated a range around 11,500 ohms; mine showed 10,500. It passed a 3rd resistance test and a continuity test. I'm not sure if my ohms readings are really that far out of whack. Hate to "throw" parts at it. Interestingly, the ohm readings Honda gives in the factory 87 shop manual are for 70F - exactly the temp I was testing in today(Saturday).

Once again, will look at igniter tomorrow if time permits.

That damn igniter is $159.28 from a Honda dealer in Rhode Island - cheapest I have found. Don't care for bone yard electrics - usually no better than what you have.

[lostforawhile]

before you spend that kind of money on the ignitor,why don't you get a junk one to test it,then you have a spare to throw in your glove box. also nappa sells the ignitor unit,I just went through this,but mine was getting flakey hadn't quite quit yet.I forget what it cost but was a little cheaper,had a 5 year 50000 mile warranty. your coil sounds fine, those ignitor units can show a resistance check fine,but be bad,thers really no way to test it. they crammed basically what was in that chrysler ignitor box and pickup into that tiny module in 86. quite a feat. and chrysler bragged in the late seventies and eighties that their electron ignition was state of the art.

[Lester Lugnut]

Ok - as mentioned above, plugs are wet(gasoline) - getting fuel. Coil failed 2 of 3 resistance tests; passed the continuity test.

Hooked up a timing light to #1 cyl wire and had wife crank it. The timing light fires, so......the cyl. is getting fire. Do the same for cyls. 2,3; 4 - hook up timing light and the timing light fires on them as well.

Now I suspect a weak coil, so I replace it with a new Napa EC115. The car still will not start and gives no sign of firing while cranking. Just to be sure, I pulled the dist. cap & noted the position of the rotor, bumper the starter with ign. switch and rotor moved, so it would seem the t-belt is ok.

Napa WEB sites shows a reman distributor "with module". The photo shows what appears to be an igniter attached to it. Cost Is $190.49 w/core, but I sure hate to thow the better part of $200 at it to get another no start.

Could a faulty igniter, pickup coil; reluctor(one or more of the 3) allow enough juice to get thru to allow the timing light to fire while cranking the engine, yet be to weak to fire the cyls.?

[Lester Lugnut]

Ok - as mentioned above, plugs are wet(gasoline) - getting fuel. Suspect coil as 2 of the resistance tests are a little weak.

Hooked up a timing light to #1 cyl wire and had wife crank it. The timing light fires, so......the cyl. is getting fire. Do the same for cyls. 2,3; 4 - hook up timing light and the timing light fires on them as well.

Now I suspect a weak coil, so I replace it with a new Napa EC115. The car still will not start and gives no sign of firing while cranking. Just to be sure, I pulled the dist. cap & noted the position of the rotor, bumper the starter with ign. switch and rotor moved, so it would seem the t-belt is ok.

Napa WEB sites shows a reman distributor "with module". The photo shows what appears to be an igniter attached to it. Cost Is $190.49 w/core, but I sure hate to thow the better part of $200 at it to get another no start.

Could a faulty igniter, pickup coil; reluctor(one or more of the 3) allow enough juice to get thru to allow the timing light to fire while cranking the engine?

[joebeets]

Hook up an actual plug and look at the spark.

[lionel]

Jumping kind of late in the discussion. May want to check the actual pump pressure and flow, at the front fuel filter and if not Ok at the output of the pump: you have access to it trough the access cover (left one) in the trunk.

Low pressure or flow can be caused by a dirty fuel pump strainer: remove the pump (through access cover) and clean the strainer in clean gas.

It happened to me but I had other symptoms (e.g. hesitation at full throttle) before I got stuck and it won't start.

As said before first check spark at plug to rule out ignition pbs.

Lionel

[Lester Lugnut]

Hook up an actual plug and look at the spark.

Did just that this evening. Each plug produced a bright spark. The plugs were sooted a bit in 2 cases and very wet in 2 others. As I checked each plug, I replaced with a new BPR5EY-11 gapped at .044.

I started at cyl #4(far left facing motor). While testing the #3 plug, I got a little bit of buck out of the motor as I was cranking it with a remote starter with ignition on. The new #4 plug was trying to get things going.

After all 4 were replaced the car fired right up.

Apparently there was enough resistnace in the plugs to prevent starting.

Thanks Joe.

[lostforawhile]

i'm glad you got it started,keep an eye on those plugs,how old are your ignition wires,cap and rotor? did you check the gap on the old plugs? maby they were gapped a little wrong

[Lester Lugnut]

i'm glad you got it started,keep an eye on those plugs,how old are your ignition wires,cap and rotor? did you check the gap on the old plugs? maby they were gapped a little wrong

I checked the gap as I removed each plug. They were still at .044 and were really not all that old. The cap/rotor/wires are all dealer parts and about a yr & a half old. I've noticed that Honda parts tend to last much longer than the after-market stuff.

My car runs rich and I suspect a bit of valve stem seal leakage. It couldn't be too bad as there's no smoke or oil loss, but you don't need much to foul plugs.
Because of the mileage(275,000) and the fact that the distributor and carb are original, I'll likely need to change plugs more often.

[lostforawhile]

I checked the gap as I removed each plug. They were still at .044 and were really not all that old. The cap/rotor/wires are all dealer parts and about a yr & a half old. I've noticed that Honda parts tend to last much longer than the after-market stuff.

My car runs rich and I suspect a bit of valve stem seal leakage. It couldn't be too bad as there's no smoke or oil loss, but you don't need much to foul plugs.
Because of the mileage(275,000) and the fact that the distributor and carb are original, I'll likely need to change plugs more often.

if your dis tributor isn't leaking oil and the shaft doesn't have any wobble or wear,theres not much in it to wear out,that shouldn't affect it much at all.