Question : 1992 Euro won't start

[Wraith]

Sorry for the new thread, could not find a suitable one.

The long story....Bought car cheap, had to replace TPS, then ran fine for several months. Started missing and even died a couple of times when stopping. Would start right back up, and miss would go away if acceleration was present. Would only miss under load at constant rpm. Changed plugs and wires, did not fix it. Soon it would not start at all. Engine turns over no spark.

Replaced crank position sensor, ECM, and ICM. There is good ignition voltage present, and ground appears good (according to multimeter). Crank sensor shows .72 voltage AC with a resistance measurement of 843 ohms, so all within spec even the coil packs (not like all three would all crap out) checked out, still no spark.

I have yet to get it to through a code my way and I am stumped. Anyone have ideas of where to go next? Any help would be greatly appreciated.

[60dgrzbelow0]

I'm paraphrasing here...but...Superdave famously once said:

"Fuel...Air...Spark... It never gets any more complicated than that!"

It might be a good idea to check your fuel pressure at the rail Schrader valve with a decent Fuel Pressure Guage while someone raises and lowers the engine RPM and then watching as it drops back down to idle. Check the results against the acceptable Fuel Pump output levels. If its low...think of changing out the Fuel Pressure Regulator first and then watching it for a while on some tests drives. On occasion, the electrical connections to the Fuel Pump harness can get sketchy and allow these pressure dropouts when the wires lose there affirmed connections. Just approach the problem by changing or looking at only one variable at a time and you'll save a lot of time and money if you get it right.

[Wraith]

Checked....No spark is the problem. Fuel compression air are all present. Will not start, can not check at rpm. I went one at a time...Threw the crank sensor at it as it was cheap. Everything tested good, no spark. New ICM, still no spark. New ECM, still no spark. No code. Good voltage at ignition source ( Bat showed 12.3 vdc and got 12.01 vdc at ignition power lead at ICM). Ground shows good. Crank sensor is providing a signal (measured in AC voltage), and resistance well within range, neither wire shows continuity with ground/carbody. Plug wires check out, but can't even get spark between towers. All coil packs measure out good and are within limits. No spark anywhere, all 6 towers.

I did normal trouble shooting, I checked fuel pressure, measured resistance of injectors, put my noid lights on injectors, checked engine compression ( which I did only because I already had the front mounts removed to get at rear side plugs ), really stopped looking into everything else once I found no spark.

[60dgrzbelow0]

Okay... Before throwing any more parts at the problem, please consider doing this:

Consider the pedigree of the vehicle relating to WHERE the vehicle comes from. By this I mean... from any of the heavily flooded areas in the USA or from the areas badly affected by the likes of storms such as Hurricane Katrina. Many vehicles and car parts from these areas can leave the new owners and parts buyers with nightmares. This is why it is ALWAYS a good idea to document this as a direct question to sellers of parts on eBay before your car parts purchases. And that leads to the next idea here.

Pull ALL of the ignition sensors' connectors one at a time and spray them down inside and out with some electrical contact solvent. This also means looking carefully along the length of the wires to either the PCM/ECM and the ICM; examining the wiring connections for either a loose contact blade, a rusted, corroded, broken or bent contact pin(s) or a loose wire(s) at their attaching points of a damaged or corroded Metripack connectors. Then methodically examine each sensor connection point for cut, crushed, shorted or broken wire(s). In particular, the CPK (3X) sensor and the wiring going from the ICM to the ECM should be VERY closely examined. In a general sense...without a completed Square Wave collapsing magnetic coil field message making a completed circuit.... the PCM will NEVER know to authorize firing the secondary coil voltage to the spark plugs. Ergo... No Spark. You might just find the culprit loose in your hand as you poke around, gently tugging and pulling on each portion of each wire and connector until either the crack or the break becomes evident. I know this is tedious... but since you have changed or replaced damn near the entire ignition system... this seems to be the only thing left to do.... except perhaps investigating the ignition key switch for broken wiring or an internal short as well.

[TGP37]

Measure voltage while cranking. Bad connections can be hard to diagnos sometimes. Especially if the break is in the cable itself, i.e. the negative cable from the battery.

It can show great voltage while at rest but drop hard during cranking. When the issue was mild it was able to provide enough to start the car and let the alternator take over. But when at low idle, which occurs when warmed up, the alternator can't keep up and the engines stumbles until it is reved up. At times it would die and be harder to start when warm as the high amps heat the bad connection up making resistence higher.

It may appear like you have a strong connection as everything powers up fine. Try wiggling the battery cables and clean the connections.

Also check the relay as a bad relay will cause no spark.

Not sure but 0.3v loss is questionalbe. You should see no more then 0.2 for such a short copper connection. Maybe a fusible link is cooked, which is nothing more then a copper line 1/4 the size of the line it protects.

You may have compounding issues resulting from 1 unresolved over time.

60dgrzbelow0 is right about the ICM. w/o a solid signal the ICM will not allow a spark. It MUST recognize the cyl1 tdc notch or else nothing happens. A bad signal or bad connection can confuse the ICM easily. It is a very sensitive sensor but strong if set up properly.