VashtheStampede

so i just got a 91 convertible.
the inside and outside are in beautiful shape,
i am deliriously happy to have an FC again.
the only problem is that the car doesnt start.
it has been stored for about a year.
the previous owner told me he had it running about a month ago.
im not entirely sure the fuel pump is running.
there is spark though, i checked that last night.
the engine cranks over and sounds like it wants to start but just can't make it.
the cranking speed is good.
for some reason, when the EGI fuse is out it cranks much slower.

all my other cars were 86, 87, 88's so im not entirely sure what i am doing with this one.

what would you check out first?

also, the battery was connected backwards for a second while trying to figure out how to install it. the headlights came up and the main fuse (100amp) popped.
ive got a new fuse but don;t know what else may have been damaged.

BlueTII

How old is the gas in the car? IF it has been sitting for a long time you may want to squirt some ATF in the spark plug holes to build some compression. You may also want to do a compression test to see if the motor is any good before wasting a huge amount of time trying to get a blown engine running.

VashtheStampede

thanks i will try that.
i can only presume that the gas is at least a year old.
i have a compression tester i will try it out today i guess.. maybe tomorrow since i don't have a helper.

VashtheStampede

well i replaced the 100 amp main fuse under the hood and checked out the fuse block inside. there is at least one blown in there, havent done a thorough check on these. it is missing the cover for the block inside by the drivers foot. im gonna see if i can find a picture of the cover so i know what the hell i am doing.

there is a strange (well i think its strange) amount of clicking coming from the dashboard. must be some relays but i dont know why they are cycling...?

VashtheStampede

heres a pic from another post of the fuse block for an s5 NA in case anyone else is looking

VashtheStampede

ok, the only bad fuse i found on the inside happened to be the first one i had looked at... the room lights fuse. the rest were ok and in correct location... damn checking for power at the fuel pump...

VashtheStampede

allright... i think the pump is actually working.
i jumped the yellow connector by the intake and with the key turned on you can hear a little whirring coming from the trunk where the pump is. i havent checked line pressure. do you think the filter could be blocked up?

nix that, i just pulled the feed line and it IS pumping fuel while cranking. i dont have any way to test the actually pressure in the line so i cant say for certain whether or not it is at operating pressure, but it is moving some gas at least.

checking plugs and trying ATF in motor...

VashtheStampede

well i took out the plugs again and put some atf in there.
it seemed to crank a little faster and i am seeing smoke from the exhaust.
hopefully that is a sign the plugs are actually sparking like i think they are.

about the plugs... they werent wet like i would have thought after all the cranking over ive been doing. these are brand new plugs bur7eq's for the leading i dont know what is in trailing but they are ngk's and do have the t on them.

is there a way to verify that the injectors are actually firing without having to take them out and test them on the bench? im concerned that they werent wet there in fuel in the line but im afraid it either isnt at high enough pressure or the injectors just arent opening... i suppose they could be stuck closed.

im heading off to work here in a couple of minutes so please throw your ideas my way i will resume work on this bastard tonight.

MARTIN

To check the injectors, remove the cas, turn the ignition to on and spin it. If you hear clicking then that is your injectors clicking right there. O btw, you gotta put it back in timing..

VashtheStampede

is there an easy way to put the cas back in the right spot? i havent got a timing light.

does removing the cas disable ignition as well? hmm. i suppose it would, eh?

is this clicking sound really audible over the engine cranking?

BlueTII

You do not pull the CAS to check the injectors.

Do a compression test. If the compression checks out then drain the fuel tank and put some good gas in it.

VashtheStampede

ahh.. a trickster eh?

well thanks i will test compression tomorrow when i have a helper around and prolly change the gas tonight. my god man, i hope the compression is ok. i dont know what kind of engine i can switch into this thing if its not. will any s5 na engine work ok? crappy thing is its an automatic. ive got no clue when it comes to auto trans...

MARTIN

You wunna bet $500? If you pull the cas with key in the "on" position and spin it, you will hear the injectors click... You simply put the crank on the yellow mark, and align the cas with the arrow on the dot when you gunna put it back in. IF you do it correctly the timing should be pretty much dead on.

Thats pretty sad that a shop employee or owner know this..

Compression is not everything, you need gas and spark. If he has compression then he needs the other 2 in order for the engine to run. By spining the cas you check both spark and injectors at the same time.

BlueTII

It is pretty sad that you are advising him to pull the CAS to check the injectors when he doesn't even know if he has a good engine. There are much easier ways of checking the injectors which do not require the timing to be messed with. For one simply apply 12V and ground to the secondaries injectors, which are accessible on the N/A, and listen for a click. You can also hear them spray if you have fuel pressure built up. Although clicking injectors does not mean that they are flowing properly. If he feels confident with being able to remove and restab the CAS then he can do it. Otherwise it will cause more problems then it is worth.

Any S5 shortblock will drop in, you just have to swap the flywheel for the counterweight and flexplate from the auto.

VashtheStampede

OOOoohhhhhhhh!!!!! you meant spin the CAS, not spin the engine!!!
that makes more sense. would the spark plugs be firing also if i did that?

thanks for all your help, ill be working on this again in an hour or so...

can i just run wires straight from the battery to the injectors or would full battery power hurt them? also does it matter which side gets + or - lead?

VashtheStampede

ok so i unclipped one of the secondary injectors from the harness and hotwired it to the battery. it clicked quite nicely. didnt sound like any gas was spraying out though. here is a dilema... the fuel feed hose was nearly empty every time i have taken it off, but with the hose pointed at a cup and cranking the engine, i was able to see that gas is being pumped through it. would it be a fair guess that the pressure regulator may not be working?

also, the haynes manual ive got says that to check the fuel pump for operation, bridge the yellow two-prong connector by the intake. (which i did) then turn the ignition to on (which i did), then it said that i should hear the pump whirring for a few seconds (which i did).

it goes on to say that if the whirring continues for more than a few seconds that the fuel system is having trouble reaching operational pressure. the pump on mine kept running for a full minute. after that i got tired of waiting and turned it back off.

is the haynes maual right about this procedure or will the pump actually keep running forever with the check connector bridged?

(looks like i will just have to get a fuel pressure gauge)

MARTIN

the secodary injectors arent the ones that spray gas while cranking and idling. Plus you are not ONLY testing the injectors. By spining the cas, you make sure the ecu fires the injectors.
IF you spin the cas, and you have spark but no inj. , then you have a problem. and if you spin it and dont have either, then you still have a prob.

VashtheStampede

yes that is true, but i wasnt able to reach the primaries easily.

your description of how to align the cas looks pretty good, i will try this.

VashtheStampede

ok, so i was able to remove the CAS and upon turning it did confirm clicks from the injectors.

my helper finally got here and i re-pulled the leading plugs and turned the engine over to witness large amounts of fuel mist shooting from rotor 2 but nothing from rotor 1.

results of the compression test are 3 even bounces at 90 on the rear rotor, but only barely visible pressure on the front one.

i am dissappointed that the engine would not run on one rotor, my turbo ran ok on only the front one...

soooo....

i assume this means i will be tearing down the motor in the very near future?
i cant think of anything else to try with no compression on the front rotor.

thanks for all your help so far, i will likely need more along the way if this is to be rebuilt.

one thing i am still curious about is why the front rotor isnt spewing gas. i suppose without adequate compression it would only dribble out a little bit?