No Start

[Floman]

New to this site and to the Taurus SHO. I just purchased a 1989 model about a month ago. Bought it cheap because it needed a fuel pump according to the previous owner. So I thought i would buy it and put a new pump in and have me a neat little daily driver. So I did the trap door mod under the back seat and pulled the pump and installed a new one. The previous owner said it would start if he sprayed a little starting fluid in the air cleaner. So when i got it home i tested it and sure enough it started for a few seconds so i thought the fuel pump was the answer, but so far it has not worked. I changed the pump and still no start. I have read some of the threads here on the site and have checked a few things and seem ok. I did not have a fuel pressure tester so i bought a cheap one on ebay and checked fuel pressure and it is 28psi constant while cranking it over. I have read on here that it should be about 38psi. I did see on several post that the Airtex pumps are not very good and wonder if thats my problem. Filter is new but i have not checked FPR. What are the next few things i need to check?
I am hoping you guys have some suggestions.
Thanks for all you help in advance!

 

[Captainblastem]

Did you tow it home? How long was it sitting? The next thing I would look at would be the injectors themselves. Since it ran for a few seconds, you do at least have spark.

If it only ran momentarily after you sprayed the fluid in there, it's quite possible that at least some of the injectors are faulty, and the only reason why your engine was even running was because of the fluid. I'm afraid I can't tell you what the normal fuel pressure should be during normal engine operation (haven't checked that yet, and it's not in the shop manual)

-Rob

 

[Floman]

Yes towed it home

According to the previous owner it had only been sitting for about a month, i suspect maybe longer, possibly 2-3 months according to inspection sticker being out for 3 months and he did say it was his daily driver.
Only speculation on my part.

I did probe one of the injectors and i got 12v on the red wire, i cant remember if it was while i was turning the motor over or just while the key was on.

I do believe the pressure at the rail is supposed to be 38psi

Thanks

 

[Captainblastem]

No problem

Though, even if your fuel rail pressure is at 28lbs while cranking it over, that should still be more than enough pressure to get fuel into your cylinders(I'm not sure how well the engine would run under load, but it should at least run at idle).

You could try checking the PWM side of the injector. With alot of vehicles, the EEC creates a signal path to chassis ground through the other wire, while the red wire is at a constant 12v. You could check this with your multimeter, or an oscilloscope. I'm pretty sure that's how it works with the SHO engine (I'm still a newbie with this particular engine's fuel system).
-Rob

 

[rubydist]

28psi v. 35psi will not keep it from starting, so that is not the answer to your no-start. As Rob suggested, you will need to check if there is fuel actually getting into the cylinders. If you crank it over for a while and remove a spark plug, it should be wet with gas. If not, then there is no gas actually getting into the cylinders. That could be a fuse, a bad pcm, a bad wire harness or ground, or injectors that are clogged up from sitting.

 

[Floman]

Thanks
I will check for gas on plugs when I get
Home today after work and post the
Results

 

[sperold]

I was going to suggest looking at the inertia switch in the trunk, but I think your 28 pound reading suggests your pump is actually pumping.

 

[Irish Pride]

Have you checked to see if there are any codes?

My first thought when I hear "needs a fuel pump" in a for sale ad is "needs crank sensor".

 

[Slo-Sho]

You could try bypassing that ceramic fuel pump resistor on the firewall as well. They are known for causing open circuit. The way it works is the car sends full power to the fuel pump for cranking then the ceramic resistor takes over to reduce voltage to the pump.

 

[Slo-Sho]

Easy way to check for crank sensor is to see if the CEL goes OFF during cranking, if it stays ON during cranking you have an ignition side problem.

 

[Floman]

Ok have a few answers here

There are no codes but probably because battery was dead when I bought the car and have never had it running yet

During cranking the CEL goes almost all the way off but seems like I can barely see it, but maybe thats just light from another one close by

Pulled plug after cranking it for about 20 seconds and no fuel smell
While the plug was out i hooked it up to the wire and cranked it and we have fire at the plug
Put it back in and cranked it some more and checked once again to make sure, still no fuel on plug

I am not sure where the resister for the fuel pump is, maybe you could give me an idea where to look

Thanks for all the help so far

 

[sperold]

Do the quick-start trick to get it running again and have someone continue putting in the quick start or some atomized gas to keep it running for awhile. Then you will see if the CEL goes out; and maybe it will run long enough to manufacture some code information.
Don't **** the starter for this experiment as you know it is fuel related (not spark) already.

 

[tery]

Good luck floman, you'll find a great bunch here with very helpful answers for everything...I had some stuff like that and it was the pcm module cause it also partly controls the fuel pump iirc.
T

 

[rubydist]

likely the injectors are gummed up from sitting for a while, since you have fuel pressure but no fuel to cylinders.

 

[Floman]

I sure would have thought that at least a couple of them would work. I mean it was not that long since it quit running.

So at 28psi it should at least idle?
I thought i saw somewhere here or internet that there had to be at least 35psi for the injectors to work???

 

[Floman]

Should the injectors be clicking while i am cranking the engine over?

Could the cam sensor keep the injectors from firing?

Thanks

 

[rubydist]

you will not be able to hear the injectors while the engine is cranking.

if you put a 12V test light across the two terminals of the injector connector you should "see a dim illumination" while cranking, according to the factory manual.

 

[Floman]

OK
I will try that tomorrow when i get home
If they dont illuminate, what should i check next?

Thanks

 

[rubydist]

then you have either a wiring or pcm issue.

 

[Black91SHO]

I'm pretty certain it's not gummed-up injectors. My second SHO sits for months at a time and starts up just fine with 306,000 miles on it.

If you're not smelling fuel in the cylinder after cranking, my money's on the ECU/PCM not opening the injectors. And that makes sense if the previous owner just suddenly couldn't start the car, but can when he sprays a fuel in the engine. It's not uncommon for them to go out on these cars.

If you're lucky enough to find a SHO in a junk yard, grab its ECU cheap and swap it and hope it's functioning. Otherwise, O'Reilly's has them for $100.

If that's not the problem, the crank sensor would be next, but it's a pain to get to. When I do the 60k at 100k, I make sure it's replaced, because they're prone to go out eventually.

Good luck.