Guys I need some help here. I got a 95 mustang with no spark... I've tested and replaced a few components. Let me start from the beginning. Its a 95 mustang it originally was a v6 automatic car has been swapped to a v8. The harness was bought from a 95. The engine harness, mass air harness, and computer are all from the same car. The tfi module and distributor were from another car but have been tested and I even tried new replacements.I've done all the no start no spark tests and I'm not getting the signal to fire the coil. If I ground out the side of the coil I can make it fire. Also the injectors are not pulsing and the fuel pump does not prime. The rest of the sensors show the reference voltage. The injectors show the bat voltage on the one side and the other side shows 8.3 volts?? I don't understand that. I've tested that the ignition module, coil, and distributor they all have voltage. Now the weird thing when I hook up the scan tool it will not communicate but when I turn the ignition on the scan tool completely shuts off (it is hooked directly to the battery) It seems like something is shorting out. The injectors do not preprime either. The transmission harness is not in the car. I have the neutral safety switch bypassed. The processor is a t4mo. I'm almost certain I have had one of these year cars run with out the trans harness. I've done it a few times in newer ones for sure. I've tested at the spout connector and it does not flash when cranked. I've probed, poked, prodded and prayed and so far nothing. All grounds have been gone over. There is a 4 gauge block to ground. Please Please some one help me. The engine is in this car is a turbocharged, 342 cu in stroker 302. I'm so close to having a running turbo car for the first time in almost 10 years I can barely take it!
1995 v8 swap issues
- Thread starter ShaunK
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search Chythars post's,he's done the V6-V8 swap.
I'm sure he'll chime in later.
do you have the ccrm in there?
that controls fuel pump operation and various other thing's.
i've never done the swap,so i'll probably be no help to you.
in the mean time,use the search function,someone with first hand knowledge will chime in later.
and,
2:SNSign:
I'm sure he'll chime in later.
do you have the ccrm in there?
that controls fuel pump operation and various other thing's.
i've never done the swap,so i'll probably be no help to you.
in the mean time,use the search function,someone with first hand knowledge will chime in later.
and,
2:SNSign:
So, you are doing the 3.8 to 5.0 swap, and the engine has not started since the swap? Or was it running and stopped running? That will affect our troubleshooting. I'll presume that the engine has not started since the swap.
Check your underhood fuse box. Make sure all the fuses are good. A short in a harness will blow the related fuse and can keep the car from running. In my case, I had a short that kept my cooling fan from running.
It may seem obvious, but go over ALL your electrical connections. Disconnect each, make sure there is no dirt on the terminals. When you plug them back in, most connectors will make a loud "click". If you don't hear a click, the connector isn't in all the way.
The 5.0 does not use the same code reader hook-up ad the V6. The connector under the dash is not used on the 5.0. There are two plugs on the 5.0 harness (normally behind the passenger shock tower) that are used to read codes.
Check your underhood fuse box. Make sure all the fuses are good. A short in a harness will blow the related fuse and can keep the car from running. In my case, I had a short that kept my cooling fan from running.
It may seem obvious, but go over ALL your electrical connections. Disconnect each, make sure there is no dirt on the terminals. When you plug them back in, most connectors will make a loud "click". If you don't hear a click, the connector isn't in all the way.
The 5.0 does not use the same code reader hook-up ad the V6. The connector under the dash is not used on the 5.0. There are two plugs on the 5.0 harness (normally behind the passenger shock tower) that are used to read codes.
No it has not started since the swap. I have went over all connections. They all seem to be good. At first when it did not start I went thru the fuses and found the eec fuse had popped. The maxi fuse in the underhood power distribution block. I do understand that the obd 2 port will not work and the older style eec test port under the hood is the one that needs to be used and that was the one I was using. Now after I swapped the fuse it did blow again so I went thru everything and rechecked it all, redid the grounds etc, This last time the fuse had not blown. I do have the ccrm hooked up and it is from a v8 model. But the ccrm gives power to the red wires on the injectors not the others that according to what I read in the wiring schematic should be a switched ground provided by the pcm. Isn't the fuel pump also triggered by the pcm? It looks like it from the diagrams I have seen. It seems the ccrm is the relay. I've even gone as far as taking the cover off the pcm and looking for burnt traces and such. Nothing I can see but it does seem to have that smell that electronics have right after they release that magic smoke that no longer allows them to work lol. I appreciate the replys this far! I've come to the conclusion that in my mind the only way the other injector wire could show power is if the pcm would be fried or there would have to be a massive short in the harness. As far as I can tell without unlooming the whole thing I see no obvious hot or melted casings.
Hissin may have some more troubleshooting tips here for you on testing the injectors. If I remember right, the injectors always receive power but they are activated when the PCM grounds each injector.
The CCRM controls power to the entire engine. If it has failed, this would be the cause of your problem. Testing the CCRM has been covered several times, try a forum search for "test ccrm" and go from there.
The CCRM controls power to the entire engine. If it has failed, this would be the cause of your problem. Testing the CCRM has been covered several times, try a forum search for "test ccrm" and go from there.
I'm thinking there could be a couple of issues, which isn't unreasonable given the swap that just happened.
If you had a spare EEC to try, that would be helpful. The lack of code communication makes me wonder about yours.
At the EEC, IIRC Pins 20, 40, and 60 should be your grounds. Look for less than 5 ohms at each. If you lose one of these, it affects the code pulling ability.
The injector's control wire might float voltage on your meter when not energized (once the ground is sent, the voltage would instantaneously fall to zero).
But there seems to be another issue. The EEC relay is functional since you have power to the engine harnesses and components.
I'd check the fuel pump wiring in/outs just to try and narrow this down:
94-95 Mustangs Electrical CCRM - Mustang-Tech
FYI, the EEC grounds the FP relay for 2-5 seconds during the prime-out. Then the dizzy (PIP) sends the command to energize the pump while the car runs.
Do you have a spare dizzy? If you do, just unplug the electrical connector on yours and plug it into the spare dizzy. Set the spare dizzy on the engine (i.e., the upper intake). Then turn the key on. Now turn the rotor (while keeping the dizzy grounded) and see if you hear the pump prime and the injectors fire. This is just a quick way to test a PIP (without having to yank the dizzy itself. This assumes your spare dizzy has a good PIP).
What kind of scan tool do you use that connects to the car battery?
If you had a spare EEC to try, that would be helpful. The lack of code communication makes me wonder about yours.
At the EEC, IIRC Pins 20, 40, and 60 should be your grounds. Look for less than 5 ohms at each. If you lose one of these, it affects the code pulling ability.
The injector's control wire might float voltage on your meter when not energized (once the ground is sent, the voltage would instantaneously fall to zero).
But there seems to be another issue. The EEC relay is functional since you have power to the engine harnesses and components.
I'd check the fuel pump wiring in/outs just to try and narrow this down:
94-95 Mustangs Electrical CCRM - Mustang-Tech
FYI, the EEC grounds the FP relay for 2-5 seconds during the prime-out. Then the dizzy (PIP) sends the command to energize the pump while the car runs.
Do you have a spare dizzy? If you do, just unplug the electrical connector on yours and plug it into the spare dizzy. Set the spare dizzy on the engine (i.e., the upper intake). Then turn the key on. Now turn the rotor (while keeping the dizzy grounded) and see if you hear the pump prime and the injectors fire. This is just a quick way to test a PIP (without having to yank the dizzy itself. This assumes your spare dizzy has a good PIP).
What kind of scan tool do you use that connects to the car battery?
Its a snap on scan tool. The injectors with the ignition on show 12 volts on the red wires and 8.3 on the others thats what confuses me. Interesting you mention the distributor I had it out trying to do just as you described. Weird thing was I could see it spark from the case to whatever ground it touched. Also I had the coil wire off and when I touched the distributor case to ground it would shoot a spark out of the coil wire. I have tried three different distributors. Two different igniton modules. I have a new computer to try tomorrow. One of the ignition modules and two of the distributors were new parts store units. The new computer is a parts store unit. I'll report back tomorrow thanksfor the advice!
Shooting a spark out of the coil when the dizzy housing is grounded is normal. If you'd turned the rotor, you should have heard the injectors fire and the pump should have started running.
Trying a new EEC sounds good. Let us know how that goes.
Trying a new EEC sounds good. Let us know how that goes.
99FiveOh
10 Year Member
I've done this swap twice, once was in a 97 V6 which required alot more BS! It was all plug and play for me and the cars fired right up. If you have the V6 trans harness, why not plug that in just to make sure?
This sounds like it's going to be one of three things: PIP sensor/ECM/CCRM. You say you tried different dizzy's, does that mean you got the replacements from the parts stores? Reman'd? The thing you'll read about reman'd dizzys is that when they rebuild them they don't change the electronics if "their" test shows them to be good. So you can end up with a bad dizzy.
I hope you figure it out though, these problems really suck!
This sounds like it's going to be one of three things: PIP sensor/ECM/CCRM. You say you tried different dizzy's, does that mean you got the replacements from the parts stores? Reman'd? The thing you'll read about reman'd dizzys is that when they rebuild them they don't change the electronics if "their" test shows them to be good. So you can end up with a bad dizzy.
I hope you figure it out though, these problems really suck!
The plot thickens.
So I tried the remanned pcm which promptly popped the 20 amp eec fuse. Hmmm, So I popped in a 30 amp magically the ccrm started functionaing normally still no spark or no fuel injector pulse. Did some more testing. Did the ccrm tests passed with no issues. Got no pip signal. SO when I tested for the pip signal I noticed that there is no pulse. I checked the ground under 5.0 ohms I checked the power getting power. I checked the coil again getting power. Now what could cause the pip signal to get grounded out? Its reading a ground there of a few volts. Has to be a short in the harness right? Anyone got any ideas?
So I tried the remanned pcm which promptly popped the 20 amp eec fuse. Hmmm, So I popped in a 30 amp magically the ccrm started functionaing normally still no spark or no fuel injector pulse. Did some more testing. Did the ccrm tests passed with no issues. Got no pip signal. SO when I tested for the pip signal I noticed that there is no pulse. I checked the ground under 5.0 ohms I checked the power getting power. I checked the coil again getting power. Now what could cause the pip signal to get grounded out? Its reading a ground there of a few volts. Has to be a short in the harness right? Anyone got any ideas?
Do the spare dizzy test again since it only takes a couple of minutes to do. If the PIP is bad, the output (which is a square wave) will be wonky.
Also, I really don't like the idea of using that 30 amp fuse. Try to put a 20 back in and see what happens.
Also, I really don't like the idea of using that 30 amp fuse. Try to put a 20 back in and see what happens.
I did the test again. Still no signal. I almost have to believe there is a short somewhere in this harness there just about has to be. If I put in a 20 amp fuse it just pops I went thru the harness and there is no visable chaffing or any visable hot spots. I appreciate all the help thus far. I've been tearing my hair out for weeks with this issue. I'm about to order an accel set up or a fast or a megasquirt. If any one has any additional input please let me know.
99FiveOh
10 Year Member
Ok, first of all, very important when working with electronics: DO NOT use a higher amp fuse to defeat a lower amp fuse's purpose!
Here's my hypothesis: There is a short and it was causing you to pop fuses. After putting in a higher amp fuse, the short popped the next weekest link which is probably a capacitor or resister inside your ECM, hence why fuses stopped popping.
Then when you installed a new computer, the circuits were complete again, so it poppped the fuses again. If fuses aren't popping anymore, you probably fried the new computer too.
If fuses are popping, that's telling you something right there. There's no need to look into anything else at the moment besides the short. And if you go spending a couple grand on a new engine management system, you'll end up shorting it out too, not a good thing...
Now, are you 100% sure ALL harnesses came from a 94/95 Mustang?
Here's my hypothesis: There is a short and it was causing you to pop fuses. After putting in a higher amp fuse, the short popped the next weekest link which is probably a capacitor or resister inside your ECM, hence why fuses stopped popping.
Then when you installed a new computer, the circuits were complete again, so it poppped the fuses again. If fuses aren't popping anymore, you probably fried the new computer too.
If fuses are popping, that's telling you something right there. There's no need to look into anything else at the moment besides the short. And if you go spending a couple grand on a new engine management system, you'll end up shorting it out too, not a good thing...
Now, are you 100% sure ALL harnesses came from a 94/95 Mustang?
Also, if you got harnesses from a wrecked Mustang the wiring could be damaged even though everything looks OK from the outside.
Yes all harnesses came from a 94-95 mustang of this I'm very sure. I obviously know that putting in a higher rated fuse defeats the purpose of having the lower amp fuse in there. I'm very familiar with how over current protection works. I appreciate the info though. As far as the short I don't understand how a short in an old harness would be any problem with a new stand alone? I've installed a few big stuff 3 set ups and they all have their own harnesses. I've owned this car since it was a v-6 car and it ran fine. I tore out the v6 and installed a carbureted 349 stroker into the car. No harnesses were cut or modified. Now in its current transformation I wanted to go turbo so I built a 342 for it. I bought the harnesses from ebay (unfortunate I know) the seller did have great feedback but that don't mean anything. There probably was a reason these harnesses were sold. Unfortunately I got to find out the hard way. I've come to the conclusion that with a few things showing voltage they should not that this harness is just fubar. I feel I could tear it apart and find the short. But in the end this system will not keep up with my goals. I appreciate all the help.
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