oil pressure problem, & what is this plug for Q?

[FredMk3]

This evening we where going to start my new engine. Filled the oil filter (relocated BTW), removed the EFI fuse and cranked the engine a couple times to see if I can get oil pressure on the stock gauge: none, zero, nada! We searched for another way to check oil pressure, we removed the bango bolt that connect the oil feed line to the turbo, no oil was comming out of there. mmmm no good. We tried to start it this way just for 1 or 2 seconds to see if pressure will build up after it's started...the engine turned on it's own for not enought time to see pressure. Seems like the CPS is off one thooth, since it tumbled a little and stalled

My question is , I'm I suppose to see pressure on the stock gauge by cranking the engine only with the starter? Been 3 years since I 've drived my supra so I don't remember how fast the gauge acted when I was starting my car. Tomorrow we'll try to hook up a real pressure gauge where the stock sender is.

My second question is where this plug goes and for what? circled in black in the pic:
it have a white wire and yellow with a black stripe wire. Come out from the wiring harness from the back of the head, maybe it goes on the other side of the block. I thought it was EGR related since I removed the EGR, but doesn't seem to be.

 

[Timmer]

I would check to make sure that your have the pressure line from the relocation kit on the engine block end going to pressure port on the filter side of the relocation kit, and that the return is going the return port of course. Also, re-check your connections to the oil pressure sending unit, to make sure it's not something simple. As to the connecter you have circled, you don't need it.

 

[drbowser3]

I think the connector is for the factory alarm horn on the firewall...

 

[Big Wang Bandit]

It also looks like the connector for the Brake Master Cylinder thing......

 

[trydrew]

I think the connector is for the factory alarm horn on the firewall...

I would second that, but my connector looks different. Same location though, and same wires I believe.

My master cyl connection looks like that, but it comes from the left fender, not the engine harness. At least on my 90...

 

[SySt]

I doubt your guage would read much if any oil pressure by cranking it with the starter. Make sure you have all of yor timing issues fixed and try to start it. If it starts clunking for more than a second or two shut it down.

 

[FredMk3]

Thanks guys for the answer so far. For the plug I don't have the factory alarm so that pretty much rules that option out. And for the brake master cylinder....it's pretty far away from it so I don't know, will check if I have something plugged on my master cylinder. What else could it be?

I'm more concern with my oil pressure problem tho! :icon_conf

 

[FredMk3]

I would check to make sure that your have the pressure line from the relocation kit on the engine block end going to pressure port on the filter side of the relocation kit, and that the return is going the return port of course. Also, re-check your connections to the oil pressure sending unit, to make sure it's not something simple. As to the connecter you have circled, you don't need it.

We already make sure that the OUT of the block fitting goes to the IN on the filter, than OUT of filter to IN block. But we'll check again to make sure. Once we saw no oil pressure first thing we've done is check if the sender was conected right.

I doubt your guage would read much if any oil pressure by cranking it with the starter. Make sure you have all of yor timing issues fixed and try to start it. If it starts clunking for more than a second or two shut it down.

Thats what' I'm thinking...we'll adjust CPS and try start it for a couple seconds. I know that the 7mgte oil system is low pressure/high volume maybe why we don't see pressure but should be enought to see some oil flowing with the starter.

BTW I don't have the stock oil filter mount with relief valve anymore since I have a Permacool rellocation kit, and I don't have an oil cooler for now.

 

[thevork]

When we started my engine after her rebuild last year, it took some time to build oil pressure. I also had the CPS a tooths off so it wouldn't start and I got no pressure just by cranking it using the starter.

Even after the engine started, it took a second of 3 before I got good oil pressure on the gauge. Remember that de gauge is also kinda slow.

-edit:
I also have that plug and can't get it to connect to anything. The car runs fine without it connected and I also did not have a factory alarm, and I also removed the egr but I doubt that wire was once going there.

 

[IJ.]

Fred: ON a fresh build I see minimum 30psi cranking with the plugs removed.

I'll run the starter in 20>30 second bursts till I see the needle rise wait for a minute then crank till I see good pressure fit the plugs then fire it!

 

[FredMk3]

thevork: that's a bit reassuring...I know that the stock gauge is slow and not 100% reliable. Will adjust the CPS correctly and start it up and see if I have pressure, no more than 5 seconds MAX if I don't have pressure cause I don't wanna fu[k my bearings, eventhought there's plenty of moly in there.

IJ: 30psi I assume it's with an external oil pressure gauge? with the plugs removed that' a good idea, will spin alot faster...mmm wonder why we didn't think of that hehe

anybody else?

as for the plug, yeah doesn't connect to the EGR since there's only vaccum line on that system except the VSV put the plug is brown.

 

[thevork]

hehe lol I just found a picture of my car from before the rebuild and even standard from factory the plug was not connected to anything! I redid the whole wiring loom and let the plug 'stick out' a few inches but from factory the plug is tight to the loom so you can hardly see it.

I attached a picture to prove it.

Does anybody know what it's for?
(It can still l be for the factory alarm as mentioned before?)

 

[IJ.]

Fred: No no no!

PRESSURE First then start it!

Even 5 seconds is enough to wipe the surface of a bearing!

seeing 30 psi on the stock gauge.

Mine takes awhile to prime as it has to fill the Cooler and Accumulator before I see pressure.

 

[Supra]

hehe lol I just found a picture of my car from before the rebuild and even standard from factory the plug was not connected to anything! I redid the whole wiring loom and let the plug 'stick out' a few inches but from factory the plug is tight to the loom so you can hardly see it.

I attached a picture to prove it.

Does anybody know what it's for?
(It can still l be for the factory alarm as mentioned before?)

I don't recall what's for specifically, but it goes to a connector that is usually on the firewall near the brake booster. It's usually 8-10" long as you can see in this photo of my87T on the engine stand (look to the right of the photo, the connector is bright white):

 

[FredMk3]

Fred: No no no!

PRESSURE First then start it!

Even 5 seconds is enough to wipe the surface of a bearing!

seeing 30 psi on the stock gauge.

Mine takes awhile to prime as it has to fill the Cooler and Accumulator before I see pressure.

Copy that IJ!!

yeah will remove all plugs and crank it. Removing plugs is a PITA with that 3k pipe in the way.
I really hope I'm gonna have pressure that way. The oil pump is brand new, didn't do anything to it. Before installing the oil pump I checked how it spinned with the drive gear and my fingers and it seemed to be fine, acted like the other 2 pumps I have here.

going to try this in a couple minutes!

 

[FredMk3]

Well guys.....Car if FINALLY running! Wow thats was a longg 3 years of wait. LOL

Oil pressure wasn't a problem after all. First thing we've done is remove the CPS and insert it like stated on JBL MK3 site(very usefull). When we remove the CPS I notice there was plenty of oil on the CPS gear....after that we crank it a bit with EFI fuse removed. Removed the oil filter and theres was trace of oil on the inlet of the filter. So I crank it with the filter remove and there was a big gush of oil comming out! Put the filter back on and started it...took like 3-5 seconds for the stock gauge to come up in pressure. Hooray!! Checked for any leaks and I sat down behind the wheel for the first 30min of break in at 2-3000rpm. Water temps was all good as oil pressure. First test is passed.

Did the first oil change and went to the gas station to fill it up with nice new fuel. lol On my way to the station, as soon as I was going pass 1800rpm there was like a fuel cut, acceleration was cut no mather what I do with the gas pedal. Got a check engine, code 41 TPS like I was thinking. Unhooked the TPS and all was good, well except that the engine tend to stall when comming to a stop and when disengaging the clutch and is not very responsive from idle. Will check the TPS tomorrow with an ohm-meter, I have another TPS here...

BTW do pre-89 TPS and post-89 TPS are the same??

Oh and I almost forgot... man this engine pulls!! and I still haven't put more than 60% throttle and below 4.5k rpm. The BIC re-rooted DDP, high flow cat and HKS Silent Hi-Power cat-back must be the reason why...and a fresh engine hehe!

 

[mk3 for life!]

just to let you know, that plug is in fact the factory alarm, I have it hooked up on mine and my buddy has it too,

 

[FredMk3]

just to let you know, that plug is in fact the factory alarm, I have it hooked up on mine and my buddy has it too,

ok thanks man...that was the more plausible option.

BTW that block in your avatar is scarry! :eek3:

 

[mkiiSupraMan18]

Fred: ON a fresh build I see minimum 30psi cranking with the plugs removed.

I'll run the starter in 20>30 second bursts till I see the needle rise wait for a minute then crank till I see good pressure fit the plugs then fire it!

I did this with my rebuild and it spun so fast I thought the starter wasn't actually engaging... Thought i was going to have to swap starters 5 mins after I had the engine sitting in the car. Talk about a relief. :icon_bigg

Even w/ stock everything it took quite a while to get good oil pressure.