1989 7mgte 5 speed no start..

[DieselScout2]

Alright, so I just picked up a 1989 supra with the 7mgte motor and a 5 speed manual.. Known mods: 550c injectors, garett turbo, upgraded intercooler/radiator, full 3 inch exhaust, walbro fuel pump, lexus afm, many electronic upgrades, boost controller, fuel pump gauge, air fuel regulator, white dash, Upgraded clutch and transmission.

So basically the previous owner went on a one month vacation, came back, and the car no longer started. Fast forward a year and we are here today. First thing I noticed was that i had a fuel leak on the fuel line to the front of the injector rail. Replaced the fitting. No leak. Now I am also not getting fuel there.. Also, to turn over the car, you have to flip the toggle switch up, and down to stop the starter. So, here are a few pictures of what I noticed around the car:



Some of these wires are cut, and I found a plate inside the car that looks like a ground strap? Is this one of the grounds that should be on the intake manifold? Any help is appreciated, thanks.

 

[DieselScout2]

 

[plaaya69]

I know those wires look like a tasty bowl of spaghetti for a mouse and it looks like one was chewing on a few for a snack. Do you have a aftermarket alarm installed?

From first post:
It looks like you may need a few fuses (even though some spots are meant to be blank). Also check all of them with a test light to make sure you are getting power.
Pic 8 out of 10. You should reground that the right way with the proper terminals that go from the coil pack bracket to the top of the cylinder head.


From second post:
Tons of aftermarket stuff going on here. Check those fuses as well and check power sources with a test light to see what is getting power.
Pic 6 out of 8. That the bracket that goes on the trans mount. One side is the hanger for the rubber exhaust o ring to the exhaust pipe and the other is a ground cable that goes to the body iirc.
Pics 7 and 8. Looks like someone did the 12v fuel pump mod so your fuel pump gets a full 12v all the time. You want to search and take a look at a basic relay wiring diagram and check power and grounds to that relay too so you know if your fuel pump is getting power or not when trying to start the Supra.

 

[DieselScout2]

I know those wires look like a tasty bowl of spaghetti for a mouse and it looks like one was chewing on a few for a snack. Do you have a aftermarket alarm installed?

From first post:
It looks like you may need a few fuses (even though some spots are meant to be blank). Also check all of them with a test light to make sure you are getting power.
Pic 8 out of 10. You should reground that the right way with the proper terminals that go from the coil pack bracket to the top of the cylinder head.


From second post:
Tons of aftermarket stuff going on here. Check those fuses as well and check power sources with a test light to see what is getting power.
Pic 6 out of 8. That the bracket that goes on the trans mount. One side is the hanger for the rubber exhaust o ring to the exhaust pipe and the other is a ground cable that goes to the body iirc.
Pics 7 and 8. Looks like someone did the 12v fuel pump mod so your fuel pump gets a full 12v all the time. You want to search and take a look at a basic relay wiring diagram and check power and grounds to that relay too so you know if your fuel pump is getting power or not when trying to start the Supra.

Awesome thank you! Did some more work last and discovered the the 10 gauge wire running to the fuel pump was connected halfway with a crimp connector, and fell off. Repaired that and now I have fuel! I will fix those grounds on the coil pack as well. Last night I also hard-wired the CPS, (I'll be doing the GM four pin connector soon). Now I have spark out of the coil but the spark plug itself isn't sparking. So looks like I'll be replacing the spark plugs and go from there. I'm new to the gas world, as my other vehicle is diesel, so I am learning as I go. Thank you!

 

[plaaya69]

No problem. Let us know how it goes and if you are getting new plugs I would highly recommend NGK plugs.

 

[DieselScout2]

Alright, all new NGK plugs and still no fire. Car does run on starting fluid as I came to find out. Stopped using that when a fireball came out the intake and singed my arm.. I'm going to put new plug wires on, and also switch a coil pack from a running supra onto mine to see if that is the issue. I'll update when I get that done.

 

[plaaya69]

If you have to spray starting fluid to keep it running then its most likely a fuel problem. A quick test to see of you are getting spark it to ground out a old spark plug with the spark plug wire connected to it to the cylinder head while you crank it over for a few seconds. You should see the spark in the spark plug.

 

[DieselScout2]

If you have to spray starting fluid to keep it running then its most likely a fuel problem. A quick test to see of you are getting spark it to ground out a old spark plug with the spark plug wire connected to it to the cylinder head while you crank it over for a few seconds. You should see the spark in the spark plug.

Grounded the #1 spark plug and it does spark. Did the test with the rest of the coil pack and found that the #6 coil is not getting any power. Used the same spark plug wire throughout all the tests so I know that the wire was not the issue. However, the #1 wire does get power. Is it possible that the ecu is not sending out a signal to the injectors due to this failure?

 

[Asterix]

Just a thought: if you have fire in the intake, maybe the spark happens when an intake valve is open. That says a timing issue.

Have you perused the TSRM?
http://www.cygnusx1.net/Supra/Library/TSRM/MK3/
It is full of troubleshooting info, especially for the ignition system.

 

[DieselScout2]

Just a thought: if you have fire in the intake, maybe the spark happens when an intake valve is open. That says a timing issue.

Have you perused the TSRM?
http://www.cygnusx1.net/Supra/Library/TSRM/MK3/
It is full of troubleshooting info, especially for the ignition system.

I have not looked through the TSRM.. I know, shame on me. Anyways, tonight I switched coil packs with a running car, no dice. Noticed a sparking under the intake manifold, and thought that it could have been the reason for my intake fire while using starter fluid... Pulled the intake, injector rack, and inspected wiring. Noticed the knock sensor above the starter was completely disconnected as the plastic piece broke/was eaten. Could this be my issue? Also when i pulled the injectors they all looked pretty dry,and some had the plastic caps missing/broken. Should I address this? I will upload pictures of my findings ASAP. Thank you, Sean

 

[DieselScout2]

UPDATE: While everything was apart, I decided to test each injector to see if they would pop. 2/6 injectors worked as they should. The other 4 did not fire at all.. Looks like I have found my problem!

 

[plaaya69]

What brand injectors do you have?

 

[DieselScout2]

What brand injectors do you have?

Absolutely no clue. I know they are 550 injectors according to the previous owner, but have no markings on them. Traced the plugs for each injector and they were spliced into the wiring. I screwed around with some carb cleaner and wires last night and somehow manages to get the other 4 injectors working again.. Putting back together this morning with a new o-ring kit.

 

[plaaya69]

Ok, just curious because RC makes some great incectors and if you have Venom injectors those are junk and cause a lot of problem's and have even ruined people's motors.

 

[DieselScout2]

So, the supra runs! It was running great, I let it idle for about 30 mins to warm up, then took it about a mile away to fill up the tank with gas. Made it back to my neighborhood, and now the car is running really roughly. It dies as soon as I give it any throttle. I'm going to check the timing, and possibly any electrical connections that could have come off on the test drive.

 

[plaaya69]

Good to hear you got it running. I would say right away check the "Cam Position Sensor" wiring/connector and with it running, slightly wiggle it to see if it changes rpms or your idle changes back to normal.

 

[DieselScout2]

Good to hear you got it running. I would say right away check the "Cam Position Sensor" wiring/connector and with it running, slightly wiggle it to see if it changes rpms or your idle changes back to normal.

I already bypassed the connector itself. Is it possible that the timing belt slipped at all? Is that common? Looks like I'm going to need to invest in a timing light!

 

[Mk3TargaJames]

I already bypassed the connector itself. Is it possible that the timing belt slipped at all? Is that common? Looks like I'm going to need to invest in a timing light!

I'd say check the MAF sensor too. I left mine unplugged and it did the same thing when throttle was given. Could also be bad/reading bad.


Sent from my iPhone using Tapatalk

 

[plaaya69]

A slipping timing belt is not a common problem on these cars. Not saying it cant happen but it is very rare. Since you got a project car it is definitely a good starting point to check the timing and go from there but just like James said a disconnected (or bad)AFM could also cause your symptoms. You do not have any codes?

 

[DieselScout2]

A slipping timing belt is not a common problem on these cars. Not saying it cant happen but it is very rare. Since you got a project car it is definitely a good starting point to check the timing and go from there but just like James said a disconnected (or bad)AFM could also cause your symptoms. You do not have any codes?

No codes right now.. The car is teasing me. It runs great for a second or two, then will return to the usual problems. I have tries unplugging the TPS and the lexus AFM(same as maf?). When plugging the afm back in the idle increases for a second, then dies down. Also, My temp gauge is not reading at all. On the thermostat housing the top sender has a wire connected to it, and if I'm not mistaken the sender right below it should have one as well, correct?