Ok, so before anyone crucifies me with 5 year old links to threads, I'm just saying I searched a few times and didn't find anything on this. My friend and I did a TBI to carb swap on his '91 RS. We got the correct regulator, ran the lines correctly and everything. We go to start it and we have no fuel coming from the feed line. In the process of swapping to carb, like everybody does, we cleaned things up and removed some old wires that are un-needed. I can't hear the pump turn on and was wondering that we might have snipped a wire for the pump or something. The fuel pump was fine before the swap and I really don't think it went bad. I know I know its probably in the Haynes Manual but I lost mine in moving garages and was searching for some help and opting to find it rather later rather than buy another. Any help would be GREAT!

(I wanna let my buddy enjoy the warm weather were supposed to get andnot feel bad as another 50 degree February day pases with us swearing over his car.)

 

 

I feel like it might be that inline fuse becasue I do remember seeing like the type of connectors for the fuse under the hood, do you know what the fuse amp is? also we did misplace a screw for the ground terminal near the battery and I feel like we might not have the pump grounded. do you know where the pump ground is? under the hood or near the tank?

 

 

ECM controls the fuel pump through the fuel pump relay. No ECM = no fuel pump signal = no fuel pump priming.

BUT - the Oil Pressure Sending Unit (OPSU) above the oil filter will run the pump after oil pressure is sensed by it. Unless 1) the fuse by the battery is blown, or 2) the OPSU is bad.

That OPSU has 3 wires, one black (feeds the gauge), one red or orange, and one grey I think. Anyway, you can disconnect the two non-black wires, and rig to a relay, so that when the relay gets a hot-in-run and a ground, it energizes, and connects those two OPSU wires together, making the pump run everytime the key is on.

Standard 30amp relay from any auto parts store:



85 = hot-in-run
86 = ground
87 = OPSU wire
30 = other OPSU wire
87a = not used

 

 

Fuel pump won't shut off anyway, regardless if still using ECM or not - 3rd gens have no emergency shut-off feature - that's something not put into cars at all until the last 2-3 years. In fact, it's a totally new feature with the 2011 Lexus (I think) - someone is making a stink about it in their new tv ads - air bag goes off, flashers turn on, fuel pump dies, doors unlock - that's a totally new feature for 2011. I'm not even sure if anyone had an emergency fuel shutoff until even this year. And they are activated by the air bag system, not the ECM.

 

Ok, so the reason why its not pumping is because of the ECM?? and I thanks for the relay tip, I'll check the ground next time we work on it. Maybe the fuse is blown? We replaced the battery cables and he hooked em up backwards and hooked the positive lead to the ground and totally fryed the wire so he sniped it and there was smoke coming from under the cowl area also. Maybe thats got something to do with it. Wiring is not my strong suit (probably why I stripped all of em out of my 91 and am swapping a BBC in...)

 

 

Yeah when he was saying it was sparking a lot i was like but with the ignition the only thing is we went to the HEI distributor and so if i wire the relay that someone was talking about we CAN remove the ECM? and retain use of stock gauges etc? Also where is the ECM fuse?

 

 

Ok, cool. But just to be 100% totally clear, becasue I'm getting paid for this...(even tho i suck at wiring) I don't wanna have anything ***ked up for him. We do have the distributor that is non ECM controlled and the rest of the car is converted to non ECM. So I will remove the ECM so I will get the fuel pump to work by wiring in camaronewbies diagrahm? and with that this thread should be closed. hah. THANKS SO MUCH FOR THE HELP!!!

 

Does anyone know about the hoses from the fuel pump to the other lines under the car. I had changed my fuel pump and now I'm getting no gas to my tbi at all. I'm thinking my hoses are in the wrong place. Pm me if you have diagrams or any help at all.

 

 

We removed the ac so I think we should be good. Where is it just so I can be sure he's got it off.

 

Not trying to be a jerk, but rather trying to help ....

We're talking about fuel pump wiring here in this thread (it is the Electronics section after all), and you're asking about fuel lines (not electronics) - two completely unrelated subjects.

We'd love to try and help you, but your asking in the wrong section, and hijacking a thread with a different subject all together.

Repost you question in the General Tech section, and give us a tad more detail on which 'hoses' you are referring to, and I'm sure we can find an answer for you.

And welcome to TGO!

 

 

ok! and nice sig. haha

 

We went down to work on the RS today and so there is no power to the pump when you jump A to E. There is power when I jumped E to 12v. So I looked into the schematic and now I narrowed the problem down to the distributor. Its an aftermarket HEI that doesn't (so i think) have the right leads to connect to the stock connectors to send a signal to the ECM to send to the green and white striped wire on the realy to kick the pump on. Suggestions please!!!!!!!!!!!!

 

 

I check what I am thinking is the fuse and it looks all good. But what IF we ran a wire from the IGNITION terminal on the fuse block to a 4 fuse circut thing under the hood. Then we could hook that up to the relay and choke and stuff like that.

 

I've got an 89 TPI car and my fuel pump is staying on after I shut the car off and I saw this thread and the suggestion of using a relay. Figured I'd all my experience to this.

I've went through about 5 OPSU's and other than the one that failed and puked out 4 quarts of oil and I almost lost the engine over that one they don't last long. The others all go bad and keep the fuel pump running. I've verified it is the OPSU that doing it. I can remove the fuel pump relay and the pump stays running, disconnect the OPSU connector and the pump shuts off.

It seems to me that 5 sensors can't be bad, something is making the contacts apparently stick or weld themselves together. Not sure why...........but can't think of any other reason they go bad so quickly.

I'm thinking of using a relay kind of like was suggested, but using the OPSU to turn the relay on and off and the relay supplies the power to the pump taking the current load off the OPSU. This would retain the safety part of the sender.

The pump was new in Dec of 09. I got the car cheap cause it wasn't running. That weekend I had a new pump in it and drove the car.

 

Ok here is my problem and I really need help with this I hav a 89 camaro irocz 305 tpi I have changed the fuel pump fuel sendin unit fuel filter fuel pump relay and I checked for a fuse for the fuel pump by the battery but there aint one there im not not gettjn power to the fuel pump it wont *** on so I dont know wat it could be but it looks lik they tried to wire up the cooling fans to where the fuse would be by the battery so whenever I turn the key the fans *** on and stay running so can somebody tell me wat my problem is

 

Someone has wired your fans to run always - 99% of 3rd gen cars get wired this way from some schmuck that is too lazy to find the real cooling problem - so you have a cooling issue of some kind - probably just a fan issue that needs coolant temp sender or fan relays or fan switch replaced. But, they've hacked up your wiring, so to make it the way it should be your going to have to rewire it to stock.

If your fuel pump doesn't run, then you have either
1) issue with ECM
2) issue with fuel pump relay
3) issue with wires to fuel pump relay or to the fuel pump.

Now - since this is a VATS car - the question is ... is the pump not running, or are the injectors not firing? Get your ear against the gas tank and have someone turn on the key - you should hear the pump prime (run for 1-2 seconds). If it's priming, then you have a VATS issue I'll bet and not a fuel pump issue. Let us know.

Also, if anyone had tied the fans into the wires for that fuse by the battery, the fans would run all the time, even with key in your pocket - so that's not the case - you just didn't find it yet and need to look again. The fuse is inside a weatherpack to protect it, has a 10ga red wire going in and a 10ga orange wire coming out. Take the battery out of the car and dig in there, you'll find it - usually it's attached to the fender, but most have come unattached after this many years.

 

Yea well thats the thing when they ran the wires for the cooling fan they spliced them into the fuel pump wires and its caused the fuel pump relay not to get power. its the orange wire from from the relay they cut the fuse off the wire were it was connected to the battery and they spliced the coolling fan wires into it so that it would *** on wen the key is turned and stay running so how do I go about fixing this problem

 

Also, if anyone had tied the fans into the wires for that fuse by the battery, the fans would run all the time, even with key in your pocket - so that's not the case

I'm lost as to where they hacked into what. Can you get us pics of the wiring mess your looking at, by the battery - and also pics of the fan relays and fuel pump relays, showing the wires going in/out - maybe can pinpoint the issue then.

 

Ok well the wire from the fuel pump relay orange that runs to the battery with an in line 20 amp fuse is that right ???? And the fuse part has been cut away from the wire and it looks lik its been ran to the cooling fans cause if I disconnect that wire the fans go off. But my main problem is this im not getting any power to the fuel pump relay is there a way to rewire this and fix this problem

 

I'm still working my problem out on my buddy's '91 but from my miniscule amount of wiring knowledge I'll say this. From what I'm reading you have you fans wired in to the wire for the fuel pump fuse near the battery. so there is NO fuse? or red wire? and did the car run before this? What I'm going to do and I'm not 100% sure if this is right, but I have a schematic from a 95 z and on it theres a terminal in the fuse block marked IGNITION, so it goes hot when the key turns on. I'm going to run a wire from that terminal to a 4 terminal fuse block under the hood, from there I'll run wires to the pump relay, choke, etc. Now thats what my dad and I did on his '70 Chevelle and everything hooked up fine. With my thirdgen knowledge you might run into trouble because it seems every owner of our cars liked to dive into our wiring and splice and re route the crap out of it. Someone please let me know if I'm on the right track or should just shut up casue I don't know what the hell I'm saying. (be honest! haha)

 

yea the only wire i see near the battery is a orange wire but no fuse on it and i know the orange wire on the fuel pump relay should have 12volt power always and its not getting nothing so im tryin to see how i go about wiring up to get power without messing up anything

 

I'd say at this point your beyond messing things up. Since your're missing a relay... but anywho did you read the previous posts? Have you checked the orange wire at the relay to see if it's getting 12v and jumping A to E and E to 12v? Let me know how that goes and we can get you back up and running.

 

Ok so I tested them no 12v on nun of the relay wires and I jumped them and wen I jumped 12v to the tan and white wire the relay made a click so I know the relay is good. So then I took a battery and took off the plug that runs to the fuel pump under car a jump power to it and it came on I got good fuel pressure up to the fuel rail but the car wouldnt crank why is that

 

You had nothing cranking? no clicks or anything? and did you jump the gray wire on the relay to the battery?

 

Yea it was turning over and it was gettin fuel to the rails but wouldnt fire up and wat gray wire are u talkin about the one under the car

 

on the relay. located at the top right part of the engine bay (looking from the front) theres two relays. The fuel pump is the one on the right I think. the wires might be dirty but there should be a gray, black w/ white stripe, red, orange, and green w/ white stripe colored wires. If its cranking and getting fuel but not starting you probably dont have spark.

 

It has spark cause if I spray starter fluid in it will start up for a few seconds and my wire on my fuel pump relay is tan with white, black, green with black, red, and orange wire

 

Wait, did are you talking about cranking it while you ran 12v to a wire under the car? and I'll double check the wires and post pics. But if you spray starter fluid and it runs and cuts off its cause you dont have FUEL!!! .

 

Maybe somebody can tell me wat to do now I changed the fuse by the battery and now im getting power to the fuel pump relay threw the orange wire but power isnt to none of the other wirws on the relay so wat could that be any help woyld be great

 

I dont know man. Maybe its the relay. I still havent figured my problem out either...

 

 

so its the orange wire, the actual wire thats the problem? Thanks

 

i got a 93 Z28 crossfire , i was having a fuel pump problem myself, i broke down and as hard as the job was i pulled the tank and found my pump had actually rusted apart and froze, i fought it for three weeks procrastinating taking the damn thing out but i found my problem

 

Yeah but on mine buddies, I jumped 12v to the gray wire on the relay, the one that runs to the pump im guessing, and the pump ran

 

On the 91 the grey wire runs back to the fuel pump, on the earlier models its a tan wire, I believe. ilovemy91camaro, it sounds like youre relay isnt functioning. Youve verified that the ornge wire is getting power to the relay and the pump works. The way to test the relay is to apply a 12v source to the relay trigger wire, which is the green wire if im not mistaken. If the relay kicks and runs the pump when you apply 12v to it, then the relay is fine and its just not getting power on the trigger.

 

 

Ok, so jump green to 12v. and if the pump runs then, its the relay. If theres no power to the orange, its wiring? if none of that applies... im ***ked?
I'll double check everything next time im over there

 

if youre not getting power to the orange wire, there's no way to test the relay. the orange wire needs a constant 12v, then the green wire triggers the relay when it gets voltage to allow the straight battery power to flow in the orange wire and out to the fuel pump. the only thing the trigger wire does is move the internals in the relay to make the connection between the orange wire and the out (grey wire). hook up the wire to a constant 12v through a fuse, then apply 12v to the trigger, if the pump runs then the relay is fine.

from the factory that orange wire is hooked to the battery via a little junction right next to the battery via a 20amp fused wire. if that fused wire got cut out during the swap, you wont ever get power to that orange wire unless you wire it back in. you can easily do that with some 14 or maybe even 12 gauge wire with an inline fuse. you should be able to pick that up at any audio place, auto store, or maybe even walmart for next to nothing.

 

ok, I'll get it figured out

 

Ok well the relay its brand new and I tested it so it clicks and open up so I know its good but my power stops at the relay so wat else can it be wat would keep the relay from energizing and mak my fuel injectors not work. Cause I hooked up a battery to the fuel pump and it got fuel pressure up to the fuel rails but it wouldnt crank and it would crank if I put starter fluid in it so wat could it be

 

Well... It starts with the starter fluid...are you injectors working properly? That's all I can come up with. You have fuel pressure at the rails though it's something in the rails or injectors. I say swap to a CARB!! hahaha

 

if someone has bypassed your starter enable relay at some point and your VATS is not working right, then the car would turn over but not start. Is the security light in the dash staying lit?