Well its started a week back ago, I blew an intercooler hose and started to get a slight miss. I replaced the blown hose that cleared up the concern or at least most of it. So steadily I've been getting a random miss, happends worse when the engines warm. I hoped in it this am cold start drove it 4 miles, and it started (i'll use cutting out for lack of better term at the moment) cutting out, almost feels like it dropped a cylinder or two. The problem wasnt initially eveident at idle, it would rev just fine in neutral. Now when its warm it misses at n unloaded rev, and just about dies when in gear. Any ideas, I'm not sure how to test the TFI module, I have recently popped two ignition coils in the laast three months so i'm thinking something is related.
86 SVO running issues
- Thread starter BELL
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goland55
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First thing I would do to eliminate some things is check the spark plugs for any significant irregularities and do a compression test at the same time. The tfi module can be checked with an ohm meter.
The layout will be like this:
GND........PIP_PWR...PIP_IN
_|..|______|..|_____|..|
...............................................--- PIP
...............................................--- SPOUT
...............................................--- START
...............................................--- TFI_PWR
...............................................--- TACH
...............................................--- IGN_GND
With the ohm meter across the following pins it should read....
GND -- PIP_IN : <500 ohms
PIP_PWR -- PIP_IN: < 2k ohms
PIP_PWR -- TFI_PWR: <200 ohms
GND -- IGN_GND: <2 ohms
PIP_IN -- PIP <200 ohms
You might want to test the TFI cold and if it tests good, throw it back on, go for a drive until it starts missing, and test the TFI warm. I know at AutoZone when I worked there a few years ago we had an ignition module tester....I'm not sure if we had the harnesses for the ford TFI (half the harnesses were lost anyway) but I know that thing would heat up ignition modules after a few tests and make the flaky ones act up.
The layout will be like this:
GND........PIP_PWR...PIP_IN
_|..|______|..|_____|..|
...............................................--- PIP
...............................................--- SPOUT
...............................................--- START
...............................................--- TFI_PWR
...............................................--- TACH
...............................................--- IGN_GND
With the ohm meter across the following pins it should read....
GND -- PIP_IN : <500 ohms
PIP_PWR -- PIP_IN: < 2k ohms
PIP_PWR -- TFI_PWR: <200 ohms
GND -- IGN_GND: <2 ohms
PIP_IN -- PIP <200 ohms
You might want to test the TFI cold and if it tests good, throw it back on, go for a drive until it starts missing, and test the TFI warm. I know at AutoZone when I worked there a few years ago we had an ignition module tester....I'm not sure if we had the harnesses for the ford TFI (half the harnesses were lost anyway) but I know that thing would heat up ignition modules after a few tests and make the flaky ones act up.
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