95 Chevy Won't Start, No spark

Hi guys,
I have a couple of quick questions. I put a 94 s-10 4.3 tb injection motor into a 95 multi- port s-10 truck. I swapped the intake and distributor and all that so every thing is 95 obd2 now.

My question is when I was swapping parts over I didn't notice that the old 95 motor had the crank senor in the front timing cover so I didn't swap it over. So now my motor doesn't have the crank sensor in front and doesn't have spark. (im chevy noob tbh)

Would this cause the dist/ecu not to spark? I have the sensor plugged in but of course it can't read the crank. I have experience with honda's and they will pretty much start up with no sensors. (run like ass but will start) Also I checked the coil and it was good and there is power to the coil.

I plan on swapping out the timing cover (might as well do the chain also) and putting the sensor in but would like to start the motor first. To work out any kinks and stuff like that.

Also last question, chevy says I need to buy a new timing cover because it COULD leak. It is really worth spending 70$ at chevy or 50$ at a local parts store if I the old one is in good condition?

Please any info would be great. This is really a great site

Thanks A lot

Josh

Any help would be great

ok josh,

reading your post it is somewhat difficult to envisualize what all you did.
but, I get you the older engine (obd1 AND throttle body) into the newer truck (obd2 and FI).
there are a slew of things that people want to question;
are you keeping the old truck, but want new OBD2 compliant? or are you just wanting the body? if so, keep it all OBD1, unless you want the fuel injection, and if so, then:
are fuel pressures/pumps equal? if not, were they swapped as well?
did you swap ECM/PCM/computers? if not why?
you mention the crank sensor, the newer ECM is looking for it, did you tap a hole or swap timing covers?
to run the EFI, you will need the harness, and the computer, at the MINIMUM, as the older TBI computer will not "talk" to the sensors correctly, also was the TBI unit controlled by a MAP or a MAF?
the FI is controlled by MAF correct?
if you do not need the FI, and you know for a fact the TBI engine was running, downgrade the fuel system to the TBI, including computer:
THIS IS THE MOST CRITICAL ISSUE:
ARE ECMs COMPATIBLE! for the '94 S10 TBI there were FOUR different computers (if it is 4WD) and these are OEM#16156647, 16184738, 16196365, and 16197427.

on the 1995 Blazer (T10) or S10 4WD pick-up with the 4.3W motor had SIX different computer possibilities, (calif. or federal emissions also) and OEM # s - 16196395, 16193495, 16230703, and a couple repeats from above, PLUS one of these ECMs cannot just be pulled and swapped, it will have to be "flashed" or reprogrammed (the 3495 one).

give us more complete run down of what all you did, or swapped, or kept, as this is probably why noone answered the post immediately;
mix and match is a nightmare in your own shop, not someone elses in virtual space. it is VERY difficult to know what all has been done.

example: (not saying this is you) guy calls on the phone, insuring my company has done something so his car doesn't run... it is broke down, and my fault, that my technician messed something up, and now it has sputtered and died on the road... I personally go with the wrecker, to examine and tow it back to the shop. pop hood, no apparent damage,
jump in, and attempt to fire it, cranks exceptionally well (as it should, we just did complete MSD package- box, dist, wiring, battery relocate, high amp alt, etc.), then I notice something on the dash....
gas light. wife borrowed car, reset odometer, didn't put fuel in, happily ever after...

so it might be a relatively simple solution, or you might have two more weeks of after work, middle of the night wrenching to finish.

you don't need to buy a timing cover if they interchange. just swap, but if they align differently, as I mentioned earlier, tap a hole in the old cover.

please give us (or me) more info, to assist in putting another Chevy back on the street.

hope this helps, or is at least a start point,
chris
nrt racing

Hi Chris (and everyone else)

Thanks for the response. I will try to make it a little bit more clearer. I have both complete trucks 94, 95 S-10 pickups. What I did is take my running motor out of the 94 and put it in the 95. The 95 motor was blown up so I took the intake, distributor of that motor and put it on my good motor out of the 94. So now the motor is converted to everything 95 obd2.

Both trucks have the orgininal harnesses and ecu. I am using the obd2 harass ecu etc that was orginally in the 95 and haven't messed with it. I just basically put a new motor in the 95 truck. But

The 94 motor doesn't have the crank position sensor in the timing cover like the 95. I assume on the obd1 the crank position sensor is in the distributor. (like a honda)

So my question is will not having the crank position sensor on the motor stop it from sparking? The harass from this sensor goes right to the coil. I know my ecu is working because there is fuel and I know the coil is good and has power. I also just planned on taking the timing cover off 95 blown up motor and put on, but chevy says to buy it new and I was wondering if it would still work.

Hope that clears up your questions of my question. I look forward to responses.

Josh

so,
it sounds like everything's been swapped into the '94 body.
'95 engine, ecu, harness, fuel and intake...
if the timing covers bolt up the same, swap it over, plug in the crank trigger and fire her up.
you can double check grounds but,
your ecm is looking for the signal from the sensor to open the injectors, and to prime and fire the coil pack, until it gets a signal, there is no way it can tell which piston is ready for its firing, so no pulse will be sent.

hope this helps,
chris
nrt racing

Hey Chris,

I swapped out the 94 motor into the 95 body. Now I have a complete 95 stock s-10. So you are saying the coil won't spark without that sensor? I have fuel but no spark.

The reason I am making a big deal out of this is because I don't want to pull the front of the motor a part to switch the cover. If I switch the cover I might as well change the timing chain also. I just really don't want to do it now considering I just did all the labor and I was to noob to notice that sensor. Just would like to get it on the road.

But sounds like from what your saying the truck won't spark because the ecu needs that sensor?

Once again thx for you help.

Josh

I was just kinda hoping to drive the truck for now, but maybe just throw some engine codes.

if using the obd2 computer, you need a crank sencor for ignition, and ALWASE alwase alwase alwase alwase replace the timing cover with a DEALERSHIP cover each time it is removed. Aftermarket covers tend to leak and so do re-used covers, you said yourselfe, lots of time invested, so why short out on a fairy inexpencive piece of insurence against an oil leak

Josh, I did the same swap as you did... Here are the facts on the swap Since you have the ODBII 95... You need to move the following from your burnt motor to the good block

Lower intake (you need that lock pin from the 95 that's on back of the lower intake)

Distributor

Reluctor wheel (big brass wheel on the crank

Timing chain cover (this holds the crank position sensor that reads the reluctor wheel)

To make the timing cover fit properly on the 94, you will see a pin on either side on the second boss down... Heat up these pins and pull them out with pliers... They're soft, they'll come out...

All your old sesnors (especially the knock sensors, not their position and make sure they are in the same position on the other block. You make have to remove some of the block plugs and use them to plug up others.


Now for the fun part... With the 95 (or the coversion you did) You're using a locked distributor... When you drop the dist in, if it is off a tooth in either direction the truck will either run like ass or not start at all. Sometimes you have to pull and drop the dist 4 or 5 times to get it right, it's a bit of a pain...

Make sure all your sensors are hooked up... Your current ecm will be fine.