'88 Civic starting problem

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Okay, just helped a buddy swap a new engine core (block and head - D15B2, if memory serves) into an '88 Civic with dual-point PGM-FI. Kept the original
intake and throttle body, all wiring appears to be back where it belongs. Engine was running before, but there was a big nasty crack down the block right behind the #4 cylinder.
We're getting spark and compression, but no fuel into the cylinders - plugs come out completely dry even after much cranking. Fuel pump is working, and there's lots of pressure both before and after the forward fuel filter. Haven't checked where the fuel line bolts to the throttle body, but I don't expect there's a problem there either.
I'm guessing something is preventing the injectors from working (again, this is the same intake and throttle body that was in the car and working previously). Didn't have any time to troubleshoot it tonight, so we're back at it tomorrow evening, so I thought I'd ask here for some pointers on where to check, what to test, how to determine where the problem may lie - any wires to check for signal or voltage, that sort of thing.
Thanks in advance!
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Does the Check Engine light come on for two seconds when the key is first turned to "II", then go off again?
Any codes stored in the ECU?
Did you reconnect the ECU ground at the thermostat?
At the bottom injector, find out which of the two wires is "hot" with the key at "II" (the other one is grounded by the ECU when it wants the injector to turn on). Remove the connector, and carefully hook up a temporary connection from the hot wire to the hot side of the injector, then ground the other side of the injector to the block or some body ground. Does the injector now spray fuel?
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TeGGeR wrote:

The connector will need to be removed to do this since if the ECU is not actively grounding the ground side, the voltage applied to the 'hot' side will appear at the 'cold' side as well if still connected to the injector.

-- Graham W http://www.gcw.org.uk/ PGM-FI page updated, Graphics Tutorial WIMBORNE http://www.wessex-astro.org.uk/ Wessex Astro Society's Website Dorset UK Info, Meeting Dates, Sites & Maps Change 'news' to 'sewn' in my Reply address to avoid my spam filter.
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Graham W wrote:

Thanks, guys... I'll take these with me to the shop. I didn't do any of the wiring re-connects so I can't guarantee anything just yet :)
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Matt Ion wrote:

Okay, buddy's testing it (I'm not at the shop, home with a tweaked back muscle today)... he says there's no power on the injector wire. It does appear to be grounded to the thermostat housing (he's checking if it's got a GOOD ground) but he reads no power coming in.
He notes there's a cut read wire hanging under the intake, coming out of a bundle along with one wire for the temp sending unit, and one for the oil pressure sending unit. There's no indication where it should go.
And now he says it looks like the ground might be bad, so he's gonna fix that and try again. Meanwhile, he thanks you for your help as well :)
He's GOT a Haynes manual for this thing, which he can't find... i'm SO much more useful with a good wiring schematic in front of me :)
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Yeah? Then check here: <http://search.ebscohost.com/Login.aspx?lp=login.asp&ref=&authtype=ip,uid
log in with username: lib password: access
Click Auto Repair Reference Center from the menu at left. Navigate to your car. There are wiring diagrams.
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TeGGeR wrote:

Sweet, thanks!
Meanwhile... he's determined there's no power to the injectors. Ground is good, but no signal into them. Waiting to see if he'll actually bother to check the ECM codes (I sent him the link from your FAQ).
Thanks again...
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Power to the injectors is from the line that comes from Terminal 7 of the Main Relay. The fuel pump and the injectors receive power from the same basic source, so the trouble is probably a disconnected wire between the Main Relay and the injector harness.
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TeGGeR wrote:

Well, I actually got my hands on the car this afternoon and, with the help of the schematic (you ARE the man!), I think I found the source of the problem: the fuel pump is for some reason sinking TONS of current and causing the voltage throughout the car to drop excessively.
Specifically: checking voltage at the injectors, I get only about 8.5V while they're activated, and closer to 5.5V when cranking. Voltage *at the battery* drops from about 12V to just barely over 8V for a few seconds as soon as the key is switched to Ignition, then jumps back up to 12V, nicely coinciding with the brief time the main relay switches on the pump and injectors. Connecting jumper cables to my running car, thus providing 14V to the system, allowed the car to ALMOST start as system voltage dropped to about 9.5V with ignition on, and 8.5V while cranking - it tried to catch a few times, but just couldn't quite fire up.
After a little more tracing, I ruled out the injectors and internal wiring problems... looking at the schematic, there are only three things on that circuit - the two injectors and the fuel pump - so I figured either there was a "near-short" somewhere in its wire (a dead short would have blown the fuse), or the pump was having issues... as it turned out, unplugging the pump lead got rid of the strange voltage drop.
So I'm thinking the pump probably has bad bearings or sleeves, or is badly gummed up, or in some other way is being prevented from turning freely, and thus is drawing excessive current, enough to drop the system voltage too low to operate the ECM and/or injectors, but not enough to pop the related fuse.
Lordco was closed by this time, so my buddy's gonna pick up a new fuel pump tomorrow... but he'll be installing it on his own, as I'll be down at the football game! :)
Hopefully that takes care of things... I'll let you know!
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Say... you don't have a bunch of voltage between the engine block and the chassis, do you? I'm just wondering how the fuel pump can drop the voltage so much without blowing the fuse.
Mike
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Michael Pardee wrote:

likewise....
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I'm wondering the same thing...
If the pump is providing adequate pressure and has worked fine before then what happens to the voltage if the fan blower is on max after the pump turns off?
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Burt wrote:

I don't know that it's providing ADEQUATE pressure... only that it's providing SOME pressure.
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Michael Pardee wrote:

I've wondered that as well... I figure it's probably pretty marginal. Thing is, the pump is normally on for only a couple seconds until you start cranking, at which point the voltage drops a lot more because of the starter.
All major grounds are checked and solid - at first there was no standard ground wire from the battery to the block, so we use a set of jumper cables, both from the negative terminal, one to the block, one to the body.
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Matt Ion wrote:

Oh, and... power readings at the injectors were tested with meter grounded to battery, block, and body, at different times (whichever was most handy for that particular instance).
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Did ANYBODY attempt the particular procedure I prescribed? (To answer my own question: evidently not.)
And does ANYBODY here EVER trim their posts?
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TeGGeR wrote:

I don't know if he tried any of the ECU readings. First thing I did when I got there was test for the injector power, since he already had the meter out, and noticed the excessive voltage drop... and proceeded to find the source of that.
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It might be just a clogged fuel pickup.
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Jim Yanik
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Jim Yanik wrote:

If that was the case, there'd be no pressure on the pump and it would spin freely; it wouldn't be drawing a ton of current.
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No,a pump trying to pull on a clogged line draws more current. It spins freer under normal loads.Simple hydraulics.
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