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TURBO FUEL PUMPS


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Researching a problem that has developed. Driving back to town from a camping trip to reload on supplies and my 89 gl auto awd 4spd start bucking and sputtering when under a load, would rev up fine when it just sat under no load. Battery went dead so I suspect an alternator is part of the problem. I figured the voltage got low enough that it couldn't supply the need volts to run ecu fuel pump etc etc. When I got it towed home, I put another battery in it and now it cracks but won't start, I hear nothing from the rear frame where the pump is, i'm guessing pump or relay.

 

Guess my question is, are the turbo and non turbo pumps the same. I work at a wrecking yard, and the Hollander system says they are different. And of course they are few and far between as far as what I can see when I look it up on our computer system.

 

I know sub's are the legos of the automotive world, so it seems surprising to me that something as simple as an inline fuel pump would vary, but maybe turbos need more or less pressure or the fittings are different.

 

This thing also sprung a leak, don't know for sure if its head gasket or cracked head, seems to me I've read a number of times, that all heads are cracked on these for the most part, and I've got 2 other 89's that are both manuals, that I know have cracks in the head, but they don't leak externally like this one has started to do. And again, Hollander says the heads are non interchangeable.

 

And the last thing is, very difficult to find an engine for the turbo, I have a spare non turbo that I've kept around for one of my other 89's, is it a straight up swap, my computer system says the ecu's are different.

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1. the fue pump for an SPFI would be adequate. If you have trouble purchasing new, you can use a ford f-150 dual tank aux external mount in-line fuel pump. for 50-100 bucks depending on where you shop.

 

2. check for coolant loss in these locations: the skinny hose that goes betwen the thermostat and the top of the block, the rubber hose coming from the turbo to the hard water pipe that comes from the driver side head, the cooling line from the turbo to the back of the manifold(remove the 4wd turbo plenum to access)the elbow hose on top of the water pump, 

 

3. a bottom end block from a carb engine will work as a replacement, 8.5:1 compression vs turbo's 7.7:1. your 89 spare engine is likely SPFI with 9.5 compression

 

The difference in compression is the pistons. You could possible swap pistons without splitting the case. I would doubt you eed to replace the bottom end as long as it was not starved for oil.

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The heads are different between the MPFI/turbo and all of the rest.  There are also minor differences in the block (extra PCV connection and threaded boss for knock sensor), but as Miles said, other short-blocks should work.

 

MPFI/turbo heads crack INTO the exhaust port/pipe, not externally where you can see without pulling the exhaust manifold.  Check the spots that Miles mentioned for leaks.  The cooling hoses to the turbo are especially vulnerable, as they are exposed to extremely high temps;  they become brittle and crack/crumble easily.

 

Before condemning the pump, do some testing first.  If you want to stay clean, connect the green diagnostic connectors that live between the lower dash trim and the steering column.  With the ignition on, these should cause the fuel pump to cycle on and off every few seconds.  If the pump doesn't come on, go back to the pump (in front of right rear fender well, disconnect the wiring connector, and run battery to one wire and ground to the other (On the side of the wiring that attaches to the pump).  A working pump should run.

Edited by NorthWet
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The pumps are different.

SPFI pump will not be adequete for a turbo,IMO.

 

Discharge pressure and flow rate are greater for the turbo one.

 

SPFI is 36-50 psi and flows 80 litres/hour at 21 psi.

Turbo is 51-71 psi and flows 95 litres/hour at 43.4 psi.

 Since max boost requires 44 psi fuel,the SPFI pump is a weakling.

 

I used an Airtex 8312 on my turbo.

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The heads are different between the MPFI/turbo and all of the rest.  There are also minor differences in the block (extra PCV connection and threaded boss for knock sensor), but as Miles said, other short-blocks should work.

 

MPFI/turbo heads crack INTO the exhaust port/pipe, not externally where you can see without pulling the exhaust manifold.  Check the spots that Miles mentioned for leaks.  The cooling hoses to the turbo are especially vulnerable, as they are exposed to extremely high temps;  they become brittle and crack/crumble easily.

 

Before condemning the pump, do some testing first.  If you want to stay clean, connect the green diagnostic connectors that live between the lower dash trim and the steering column.  With the ignition on, these should cause the fuel pump to cycle on and off every few seconds.  If the pump doesn't come on, go back to the pump (in front of right rear fender well, disconnect the wiring connector, and run battery to one wire and ground to the other (On the side of the wiring that attaches to the pump).  A working pump should run.

I've read the reference to the green diagnostic wires in some other posts. I'm not a small guy by a long shot lol, so I tried to cheat and just go out to a similar (90 loyale) and look at one that already had most of the dash taken apart, I guess i'm just not seeing the 2 wires were talking about, is it 2 individual wires not currently plugged into anything else and just need plugged into each other?

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I normally defer to Miles, who has much more everyday experience than me, but I do not think he is correct on this.  The firewall location is correct for SPFI, but I am reasonably sure that all of the turbo sedans and wagons are inside the passenger compartment.  My 88 Turbo wagon does not have the connectors at the firewall.  On the other hand, Miles is usually right...

 

Anyway, if they are where I think they should be, they would not be under the dash on a 90 Loyale unless it was a turbo.

 

The single-wire green connectors are not attached to each other, but they are probably taped and stuffed against a larger harness.

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If you go the mpfi EA82 NA engine the turbo side head needs an oil supply hole drilled and tapped to M10 1.25 or maybe it is 1.5 pitch, must check, it is coarser thread, to accept the factory banjo bolt. Also needs an oil return hole drilled to take the return pipe or spike the sump! Timing needs to be reduced about 8 degrees initial to make up for the increase in compression ratio from 20 to 10 for 3 plug ECU's not sure how you set the 4 plug ECU timing reduction.

When an EA82T left the factory it also had a small difference in exhaust valves , but most aftermarket supply same for all EA82

 

As for pump, it helps to tap pump body with a hammer while someone cranks engine over.

Edited by jono
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Okay, thanks for all the input guys. Here is what I found. Not sure what exactly it is but it fixed it. Under the hood there is small perhaps 3 or 4 inch x 1 inch black box (looks like a fuse holder) and its mounted to the coolant reservoir. It has a top on it that doesn't give any type of identification as to whats inside it. When I pop the top off, it had what looks to me like 4 fusible links, when I inspected those I found the rear most one had corroded through and broken off. I went out into our yard pulled one out and after work stuck it in and voila, fuel pump started working. Needless to say, considering all the other possibilities, I'm thrilled. And thank you guys very much for your input.

 

Next thing to conquer is the blinking power light 16 times, and the leak, and I will be golden!

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Most likely last post on this particular post, just wanted to give it some "closure". One of the notes I had made a reference to the leak that had sprung up on me. I found a hose that runs from the top of the water pump under the compressor bracket and curves to connect to what I am assuming is a hard line related to my heater core. It was very soft and only seemed to really let loose on the antifreeze after getting it up to temp, and then if I let it set for about 2 minutes, poof big puff of steam and then I could watch the antifreeze follow the brackets under the alternator and run right down the center of the timing cover. Replaced it with a form fitted one from napa, drove all over in the mountains this weekend and barely had to add more than a teaspoon of antifreeze, vs. the half gallon I had to put in every time I went far enough for it to get up to op temp.

 

Thanks again to all of you for your help

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