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Hi, my name is Caspar I live in Norway. I have bought a complete TPI from (I think) a 91 Camaro and a wiring from Painless Wiring. The plan is to install it in my 55 Jeep CJ5 (3A body). I have some question, I hope someone can answer.
This is the parts. The fuel inlet is on passangerside, and the cover over the distributor is in plastic. Will that means that the parts is from a Camaro? The ECU is labeled 01227730 and the system have MAP sensor, not Air mass sensor.
And this is the engine. It’s a 307 taken from a boat, in very good condition.
Standard, but with a camshaft for torq/off-road.
In the wiring it’s a cable that connects the oilpressureswitch with the fuelpumprelay. Techsupport PW told me that signal from the oilpressureswitch was necessary for the ECU to detect that the engine was running (Cranking) There is also websits that’s says that this is a safetysytem that cuts off the fuelpump if the engine looses oilpressure. Acording to this wiringdiagram I cant understand how this is possible. For me it looks like the wiring trough the oilpressure switch is connected in parallel compared to the main circuit trough the relay, and seems to be a sort of backup if the relay fails
ECU in European cars starts the fuelpump for 3-5 seconds when you turn the ignition on, and then wait for the Hall signal from the distributor before its starts permanently
In the harness from PW is it also a cable from the starter to the fuelpumprelay, that powers the fuelpump direcly from the startmotor during cranking. Should this be required?
What is the purpose of this extra wiring trough the oilpressureswitch ? Is it only a backup for the relay?
And I cant find the wire from the starter on any GM wiring diagram, so why have PW installed it?
The oil pressure switch is a safety. No oil pressure means no fuel pump voltage. This prevents a crashed or rolled-over car from continuing to feed fuel pressure to a leaking fuel system.
This is the parts. The fuel inlet is on passangerside, and the cover over the distributor is in plastic. Will that means that the parts is from a Camaro? The ECU is labeled 01227730 and the system have MAP sensor, not Air mass sensor.
Looks like a fun project.
For the US the fuel inlet in the picture is on the drivers side. It's those crazy Brits that drive on the wrong side of the road Between that and the plastic distributor cover it is from a Camaro.
In the wiring it’s a cable that connects the oilpressureswitch with the fuelpumprelay. ...For me it looks like the wiring trough the oilpressure switch is connected in parallel compared to the main circuit trough the relay, and seems to be a sort of backup if the relay fails.
You are entirely correct. If the relay fails or the transistor in the ECM fails, oil pressure will activate the bypass switch and turn on the fuel pump. This is usually noticed as long cranking times, need to have some oil pressure to turn on the fuel pump.
ECU in European cars starts the fuelpump for 3-5 seconds when you turn the ignition on, and then wait for the Hall signal from the distributor before its starts permanently
The ECM will run the fuel pump for about 2 seconds at key-on. Once the engine is spinning (crank or run), the distributor will be sending reference pulses to the ECM. The ECM receiving these pulses will activate the fuel pump relay.
If the reference pulses stop being sent to the ECM, such as an engine stall, the pump will run for 2 seconds then shut off. Note that on a cold start and a short run (say 15 seconds), the slow dropping oil pressure can continue to run the fuel pump for several seconds.
In the harness from PW is it also a cable from the starter to the fuelpumprelay, that powers the fuelpump direcly from the startmotor during cranking. Should this be required?
Not that I know of.
And I cant find the wire from the starter on any GM wiring diagram, so why have PW installed it?
GM didn't do that, my guess is that PW did it to ensure that the fuel pump turned on during cranking. It isn't required as the ECM will do that.
Looks like an awesome project! I am just buttoning up all the little odd ball pieces left on my TPI swap into a 67 Chevy pickup. My standalone harness did not include the Oil pressure connector either, so I didnt worry about hooking it up. Not too concerned about it as I dont really see the benefit of the safety precaution in my setup.
The oil pressure switch is a safety. No oil pressure means no fuel pump voltage. This prevents a crashed or rolled-over car from continuing to feed fuel pressure to a leaking fuel system.
Best wishes with your EFI swap.
I have tested the oil pressure switch on a 1991 TPI speed density with ECM 7730 and it won't shut off the fuel pump if disconnected during crank, warm-up, cruise and hot restart (simulation of 0psi oil pressure). The ECM actually drives the fuel pump all the time. This is consistent with the wiring diagram. I believe that the oil pressure switch is there for back up in case of fuel pump relay failure or ECM malfunction. Like RBob said, it would take longer cranking in that case. If I remember it engages at 4psi but don't quote me on that.
The trottle body have water by pass probably ment too keep the the trottle body warm during cold weather. Do I need this? I never use the car in cold weather, I think its 10 year since I had the soft top on
The trottle body have water by pass probably ment too keep the the trottle body warm during cold weather. Do I need this? I never use the car in cold weather, I think its 10 year since I had the soft top on
No you don't need to use it. I would reassemble everything with new seals and not connect any coolant hoses to it.
Number 2 is from the engine harness itself. I believe the one from the distributor to the coil tells the coil when to fire, and the coil gets its power to fire from the battery through the harness plug.
The trottle body have water by pass probably ment too keep the the trottle body warm during cold weather. Do I need this? I never use the car in cold weather, I think its 10 year since I had the soft top on
You definitely know your stuff! The coolant is to keep the throttle blades from icing in high humidity and low temperature. It is usually bypassed.
However, you DO need the Idle Air Control (IAC) part of the housing. Either bolt the whole thing on as-is and don't hook up any hoses, or cut off the nipples, or cut the housing down to just the IAC part.
Originally Posted by Caspar
Its 2 simular conectors on the coil. Whats number 2 for?
All the acessory drive parts, alternator, servo pump, etc. on the engine lefts side because the eletrical fan need the space on the rigth side. I wil ost some more pics when all thr parts are fitted
I just cut the original fuel line and drilled out a hole to 9,2 mm and cut treads 1/8-28 BSP and used a standard fiting
The trottle body was damaged (collision) so I bougth a another. They are different in the ideling passage. It looks like the new one need a triangel hole in the upper pleum too be able too let the idle air get in to the plenum. Can I just make a hole in the plenum, or do I have too find a trottle body with the same design as the original?
Idle air opening
No opening in the upper plenum for the triangel hole
I like the 307 engine.They get a really bad rap, but, it's mostly due the heads GM used with them.Which heads are you using? We've had really good results using the L30/305 Vortec heads on 307 builds.They won't work with your TPI tho w/o a vortec base.
Since you say this came from a boat, you very well may have an OMC (Outboard Marine Company) built 307.OMC bought the tooling from GM after GM ended production of the 307.They produced them for some time in their line of boats.They were some stout little engines.
Last year me & a friend built a 307 for his son's 69 ElCamino using the L30 heads, Comp's XE262 cam.The Camino weighed in at 3300 lb.He was turning 13.40 in the quarter.This was also very streetable setup.
You'll be fine. The milled slots, right where your pencil is, will allow the idle air to "leak" into the plenum.
ETA: Or if that is the old, busted TB, and the new TB is the bottom picture, then drill a hole, mill slots, just do something to let the idle air from the TB "triangle" into the general plenum space.
FYI: You have a later Speed Density plenum, where the idle air just enters into the main throttle airstream.
The older MAF systems (85-87? or 88?) had a more elaborate passage system... from the TB, into that triangular passage in the plenum, to a separate tube on the passenger side runners (which the later 88 or 89-92 runners do NOT have), to the intake base, under the main ports, to a little hole on the floor of each port.
- This allowed idle air distribution to each runner/cylinder.
- For split BLM in LT1/LT4/Miniram, ULTIM8Z made a distribution plenum to replicate the older, factory idle air routing...https://www.thirdgen.org/forums/diy-...ram-split.html
i have been busy helping my son with his engine swap in his TJ, but now its time for my old TPI Jeep again. I bougth a Snap-on MT2500 scanner but I cant read anything from the ECU. I have tested the scanner on a 85 GM Astro and its operates perfect. I have connected the cabels from the ALDL connector to the ECU correct (I hope) but the scanner do not communicate with the ECU, what can be wrong?
08-12-2015, 12:59 PM
Between that and the plastic distributor cover it is from a Camaro.
