Injector Alternatives

[Edahall]

The injectors on my 93 Allante N* are super expensive so I was wondering if there's a lower cost alternative such as injectors from another brand of car?

The engine has 64k miles but I have not been able fix the hard warm start problems so I'm thinking it's probably injectors.

Symptoms:
Easy cold start
Easy warm start if started immediately after shutdown
Excessive cranking if engine sits for 15 minutes to 1 hour
Raw fuel smell from exhaust after excessive cranking
Poor city fuel economy (9-11 mpg)
Poor fuel economy at speeds under 80 mph

What I've done so far:
New AC Delco FPR
New wires
Regapped original spark plugs
New fuel filter
Ran Lucas fuel treatment through several tanks of fuel

Performed a fuel pressure test and got the following:
Cold engine - 0 psi
key on - 40 psi
5 minutes - 36 psi
25 minutes - 30 psi
105 minutes - 20 psi

[dalamak]

i used LT1 24lb Accell injectors on my 97 Cadillac, Ran great

[Edahall]

Originally Posted by dalamak

i used LT1 24lb Accell injectors on my 97 Cadillac, Ran great

I found what looks like the ones you are talking about.
http://store.summitracing.com/partde...5&autoview=sku

Will they fit and will the plugs work? It looks like there's a standard.

[submariner409]

BEFORE you buy a set of injectors, check the FPR (Fuel Pressure Regulator). A ruptured diaphragm in that will give you an excessively rich hot start, with a stumble and miss and lousy gas mileage.

Your FPR may be inside the intake manifold, so the check is no piece of cake.........

[Edahall]

Originally Posted by submariner409

BEFORE you buy a set of injectors, check the FPR (Fuel Pressure Regulator). A ruptured diaphragm in that will give you an excessively rich hot start, with a stumble and miss and lousy gas mileage.

Your FPR may be inside the intake manifold, so the check is no piece of cake.........

I initially believed it was the FPR so I installed a brand new AC Delco FPR but it didn't make any difference. But that doesn't mean that the new FPR also may be bad.

[submariner409]

Very slim chance that the new unit is faulty. To test it, do a running engine fuel pressure check with a gauge. Somewhere close to 44 psi. If not, maybe fuel pump. (Look up that fuel pressure spec - some engines vary.)

[Edahall]

40 psi max is what I get. I'll look at my manual to check what the specs are.

[Edahall]

The specs according to my manual are between 40-50 psi.

When I turn on the key, the pressure gauge goes up to 46 psi and settles down to 40 psi. When I start the engine, the gauge settles down to about 38.5 psi. If I rev the engine, the gauge will spike up to about 45 psi. I wonder if it's possible that a weak fuel pump might be causing hard starts after 15 - 60 minutes of sitting.

[zonie77]

There is a checkvalve in the pump assembly. It looks like yours is leaking slightly. The pressure seems to be on the low threshold. It might be worth replacing the pump.

[dalamak]

Originally Posted by Edahall

I found what looks like the ones you are talking about.
http://store.summitracing.com/partde...5&autoview=sku

Will they fit and will the plugs work? It looks like there's a standard.

Yeah those are them, except back when I got them they were Yellow.

Yeah the Plug ends are the Same, nozzle spray pattern is differnent and the Caddy ones on my 97 had a plastic Nozzle cap on them and what looked like only one Spray hole, the LT1 ones don't have this plastic extended nozzle cap, and have a mulit spray nozzle , but like I said car ran great!, mine came outta my 96 trans-am, so I bought the Injector o-ring kit for the caddy and changed the upper and lowers just cause the caddy on's looked a little thicker, it was like 8 bucks for the bag of them. I don't know if you're car had the recall for the plastic fuel rail, my year did so I got the S/S one for free which was a much better fit.

I didn't reinstall the CLips to hold the injectors to the Fuel rails, I never do, if you do or don't just preasureize the system before starting it and check for leaks