Air, Fuel, Weak-then-No Spark
04-28-2010, 08:37 PM
#1
CF Veteran
Thread Starter
Air, Fuel, Weak-then-No Spark
the stroker is fully in-place and ready to go now.
So we install the new fuel injectors and go to crank it; and guess what?
It just turns over without cranking. Exactly what I expected.
We weren't getting ANY spark (the battery was old and had to be recharged numerous times in the past few months in order to get it to crank without jumping it). So we went and got a new battery later on after charging it... but first---
---We went to put in the new FI's from summit racing (30lbs) and they wouldn't hold the pressure at the fuel rail. They just dumped gas into the cylinders like they were some sort of open valve. We turned it over numerous times while my friend was checking the voltages in the bay and looking for spark. The number 5 Cylinder shot out a cylinder full of fuel when took all the spark plugs out and turned it over to try and clear out all the gas. It scared the be'jeezus out of me because I was right in the bay. I wasn't expecting that.
We put the stock 19lbs back in and they held pressure. Could that have been just one bad fuel injector that didn't hold the pressure? I don't know what the fuel rail pressure reading was when we did this.
I replaced the battery with an Optima Red Top and it would start off with a little spark then die out real quick (at the distributor without the cap). Any clues as to the spark issue?
I also installed the heater core (we all know this involves the dash removal) and I reconnected everything with the exception of the one vaccum hose that runs into the AC/Heat **** (just controls the climate). All grounds both inside and in the engine bay were reinstalled.
. . . .would putting a ground against another ground that it originally wasn't grounded with have an influence on operation? Everything seemed to only fit in one area, but right over by the AC compressor (it's a 98 limited XJ) and alternator there are 3 grounds but only 2 studs in that spot. I wasn't sure how those went on since me and my dad took parts off the old engine to put on the new and he did more than half of that (to include the distributor he probably washed). I never touched the distributor so I don't know if there is anything going on in there.
.. and yes the number 1 cylinder was at TDC with the 1st spark plug, it was checked, double checked, and tri-checked.
The only electrical thing I am not sure on is in the dash compartment behind the AC ***** area (again, something else my dad did; he lives in seattle and he flew back there 3 days ago) there is the one black electrical connector that plugs into the fan-**** on the **** display, and right there at that part of the wiring harness there is a little white connector in that same spot that comes off with nothing to plug into...
It has 5 holes in a row with only the middle 3 having metal contacts in it. There's no where for it to go on the ECU and I looked for a place for it to go when I was installing the dash and there wasn't a place at all; not to mention there's only about 4 inches of space for it to reach from the same taped-together-wiring that plugs into the ****. .. . .. any clues?
Clueless Because of Seattle,
Wayne
So we install the new fuel injectors and go to crank it; and guess what?
It just turns over without cranking. Exactly what I expected.
We weren't getting ANY spark (the battery was old and had to be recharged numerous times in the past few months in order to get it to crank without jumping it). So we went and got a new battery later on after charging it... but first---
---We went to put in the new FI's from summit racing (30lbs) and they wouldn't hold the pressure at the fuel rail. They just dumped gas into the cylinders like they were some sort of open valve. We turned it over numerous times while my friend was checking the voltages in the bay and looking for spark. The number 5 Cylinder shot out a cylinder full of fuel when took all the spark plugs out and turned it over to try and clear out all the gas. It scared the be'jeezus out of me because I was right in the bay. I wasn't expecting that.
We put the stock 19lbs back in and they held pressure. Could that have been just one bad fuel injector that didn't hold the pressure? I don't know what the fuel rail pressure reading was when we did this.
I replaced the battery with an Optima Red Top and it would start off with a little spark then die out real quick (at the distributor without the cap). Any clues as to the spark issue?
I also installed the heater core (we all know this involves the dash removal) and I reconnected everything with the exception of the one vaccum hose that runs into the AC/Heat **** (just controls the climate). All grounds both inside and in the engine bay were reinstalled.
. . . .would putting a ground against another ground that it originally wasn't grounded with have an influence on operation? Everything seemed to only fit in one area, but right over by the AC compressor (it's a 98 limited XJ) and alternator there are 3 grounds but only 2 studs in that spot. I wasn't sure how those went on since me and my dad took parts off the old engine to put on the new and he did more than half of that (to include the distributor he probably washed). I never touched the distributor so I don't know if there is anything going on in there.
.. and yes the number 1 cylinder was at TDC with the 1st spark plug, it was checked, double checked, and tri-checked.
The only electrical thing I am not sure on is in the dash compartment behind the AC ***** area (again, something else my dad did; he lives in seattle and he flew back there 3 days ago) there is the one black electrical connector that plugs into the fan-**** on the **** display, and right there at that part of the wiring harness there is a little white connector in that same spot that comes off with nothing to plug into...
It has 5 holes in a row with only the middle 3 having metal contacts in it. There's no where for it to go on the ECU and I looked for a place for it to go when I was installing the dash and there wasn't a place at all; not to mention there's only about 4 inches of space for it to reach from the same taped-together-wiring that plugs into the ****. .. . .. any clues?
Clueless Because of Seattle,
Wayne
04-29-2010, 08:27 PM
#2
CF Veteran
Thread Starter
It was the ignition coil, which had a crack in it. Thanks for all your help and support guys!
... oh wait, wrong forum.
Wayne~
... oh wait, wrong forum.
Wayne~
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