as most of you have seen ive been having problems with spark. in fact i was getting no spark. i had relocated the battery, replaced the ignitor and coil, etc. to no avail i still had no spark. after reading a topic today i tried redoing my transmission ground and guess what im getting a very weak spark. i had a friend crank the car and i get NO spark. but when he turns the key out of the on position or accessory position one spark plug will spark. he can turn it on accessory then turn it off and ill get a different spark plug to spark. usually rotating back and forth between the two. then moving to the other two that have not spark yet, back and forth goes the spark and so on. well obviously it is a grounding problem. so heres what i have so far for grounding

1. i have two transmission grounds, they are both 4g wire both running from bolts that seem to hold the transmission to the block. one end is then tied to the chassis, and the 2nd ground to one of the chassis "transmission moter mount holder."

2. i have the thermostat ground. this is where im connecting the ground for the wire harness to the thermostat. im not sure if it matters but there are two places that you can put this ground. one seems to be on the actual thermostat, and the other seems to be more on the block. im sure one of these holes were originally for an arm that would hold the wireharness in a certain place, but i do not have it on there so i have two empty holes to use. which ones are you guys using? does it matter?

3. finally the valve cover, which im kinda leaning on this as to why im not getting constant spark. if you look at where i have my ground on the valve cover you will see the bolt on top then i have the ground then the black circular thing then you have the valve cover. should this ground actually be under the valve cover instead of inbetween the bolt and the black circular thing? if i put it under the valve cover wouldn't that cause a leak? sorry i don't know all the specific terms to these parts, bare with me.

im sorry if this has been covered a thousand times, but i would just like the reassurance that hopefully ill get this right. also, i would try these things already if i didn't live so far away from the place where im actually working on my car. thanks to anyone who can help.

 

I went outside and looked at my grounds and came up with this just for you.

Transmission grounds-Use both wires and ground at stock location under battery.

T-stat ground- pick a hole.

Valve cover-Remove 2 crown nuts from timing belt side of valve cover. Make new chassis ground. Somewhere near coolant resevoir will work. Do not ground from
spark plug cover.

Remember that current passes on the outer surface of the wire. You want the wire
that looks "hairy" when you strip it. Make sure you groung to direct metal.
Remove all dirt, paint, and whatever else. Dirty/loose connections=resistance.
If you're sure your grounds are clean and tight. Recheck ignition wiring/components.
Help this helped.

 

so should i try and put the ground under the valve cover in between the block? is that where you have yours located? thanks for the help

 

I think the ground going from valve cover to the rad support is just fine. I upgraded mine to 4 gauge as well but kept the same locations

 

there should be two grounds on the valve cover. One should be on one of the valve cover bolts, on top of the grommet. this one grounds the head through the valve cover bolt. then there should be another ground on top of a bump/nipple type thing that grounds directly to the valve cover. These are not crucial.. you can totally disconnect them and the car will still run.

on the thermostat housing, make sure that your ground is connected to the thermostat housing, not the block. this is crucial as this is where the ECU gets it ground. if improperly connected, your car *WILL NOT* run.

As far as the transmission grounding point, there is a small hole located on the clutch cable bracket. This is where the ground wire goes.

Make sure all your grounds are connected with crimped terminals, sanded to bare metal with no dirt or paint. make sure the chassis is free of paint and other debris at the grounding point as well. if the factory grounds are looking "not so fresh" then replace them. I would recommend that sexy ground wire that you get with an amplifier kit, simply because its easy to find, larger gauge than stock grounds, and looks good too.

hope you find the problem.

 

thanks alot guys. im gonna give all your thoughts and suggestions a try.

 

okay i got to work on the crx again. i believe i have all the grounds i need in the right place. i took some pictures just so you guys could check them out too.








also, i switched around the two white wires and one way i would get spark and the other one seemed to not. so left it the way to where i would get spark, of course. but heres a pic, i kept having to change them around the whole time so i just hardwired the wires to the distributor, but i didn't think it would matter as of right now until i got it to run. then ill put the gray clip back on.

 

also, does it seem odd to anyone that when i crank the car to start it i don't get any spark. but when i turn it off from accessory and then back to accessories it will give me one spark. i think my grounds are good enough but does anyone have any idea why my spark might be only activating when i turn it back in and out of accessory

 

the first pic where u mount the ground try to take that off and sand the paint way a lil and see what happens and the same for others, the end where u mount on to paint wont work

 

it looks like u did sand the paint off at the first pic am i right ?

 

yeah actually. on the valve cover the ground on the left where it meets the chassis is sanded down quite well and then where it connects to the valve cover there is an absence of paint from where the stock ground was. i didn't take any more paint off the valve cover cause i thought it would be sufficient since the stock ground was there and it didn't have any problems acting as a ground in that spot. as for the second ground on the valve cover, it is attached to the chassis in the same place as the other ground but it is sitting under the nut and on top of the black gromet.

im pretty sure my thermostat is hooked up in the right place.

and for the tranny ground, is the place where i have it connected to the tranny sufficient enough to act as a ground?

 

that is a OBD-1 distributor, what ECU are you using? you can repin a OBD-0 distributor to work in OBD-1, but you CANNOT run a OBD-1 dist, on OBD-0, we need more information to tell

 

i had so many topics which listed my setup i just assumed everyone on the board knew heh

anyways, its a 88 crx hf with a 93 b16a obd1 engine (pr3 ecu). the car is converted with blown90hatchs obd1 conversion kit. anything else anyone needs to know just ask. ill be happy to let you know.


Modified by Origin at 3:05 AM 6/20/2004

 

oh and buy the way, when i do turn the car to accessory i do get a cel. it doesn't blink, just constantly turns on. which would mean bad ecu/limp mode but i cranked my girlfriends car with it no problem. so i don't believe i have a bad ecu.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by daidilus &raquo;</TD></TR><TR><TD CLASS="quote">that is a OBD-1 distributor, what ECU are you using? you can repin a OBD-0 distributor to work in OBD-1, but you CANNOT run a OBD-1 dist, on OBD-0, we need more information to tell</TD></TR></TABLE>

hmmm.. if i read everything right, im gonna have to agree. you may have used a conversion kit to fit obd1 plugs, but ur still using an obd0 ecu with obd1 dizzy. i tired to do that first on my setup [94 ls obd1 block]

initially, it would make a loud spark, so i fixed the grounds [btw ur grounds look right to me]

then... it would crank but wouldnt turn over [like it wanted to start but couldnt stay running]

the problem was i was using an obd1 dizzy with a pr4 [pr4] obd0 ecu.. swapped my dizzy out to a ob0 LS dizzy. started like a champ...

hope this helped.

 

well the swap was sold to me as a complete swap so the ecu should be obd1. also its got to be obd1 because im using blown90hatchs conversion harness which mates the obd1 ecu to the crx's harness. everything about the car to my knowledge is correctly hooked up to properly run obd1.

 

my bad y0. theres a couple of pr3 ECUs

theres the obd0 pr3

and the obd1 pr3-j01

good luck..

 

i thought thats what you were talking about. no problem though, anyone else?

 

 

it looks as if the tranny ground is connected to the battery. does the tranny ground need to flow all the way to the negative terminal on the battery?

 

we had the exact same problem on a ZC swap into a hatch...

sparked only when the key was removed...we fixed grounds, swapped dizzy wiring everything....

turned out to be a bad ECU...chaged that and it was all good.

 

hmmm... i do have a full cel. i wonder if it really is a bad ecu. i tried my girlfriends ecu before and it didn't work, but maybe now that i have this ground fixed i might have a better chance at getting it to spark. thanks for the input. ill give it another go.

 

you could have a bad coil or have it hooked up wrong, when i did my swap i somehow had the coil hooked up wrong and when i turned the car to the on position a loud discharge would come from the distributor.

 

the problem is in the wiring...

what harness did u use?

engine = obd1 93 harness?

engine to ecu harness = OEM HF?

Get some wiring diagrams of the HF harness. The dist plug on the HF's is pinned differently then Si.

 

car is 88 crx hf. using blown90hatchs obd0 to obd1 conversion harness. using stock hf harness with modified obd1 plugs. i have color matched the distributor wires. and have switched the 2 white wires around everytime i do something different to the car. everything wire related is from the crx hf except the ecu and the conversion harness.