C0RR0SIVE
Golden Master
- Messages
- 9,213
- Location
- Lexington, KY
Nah, don't work at the dealer, just have a GMC Sonoma, and a Haynes manual, along with a few other books that also cover your Jimmy, as well as 10+ years working on several dozen different cars for family and friends. Almost have my own little garage here with cars in and out daily now.
If you could get me a good picture of the engine bay from an overhead position, I would know for sure what kind of ignition system you have, pretty sure it's EDI from your description.
Aside from ignition related components, we could have an issue with proper fuel delivery, but I would prefer all electrical components on the spark side are operational before we poke at possible fuel delivery issues.
BTW, while most hate Haynes booklets, I find they are rather great to have handy because they DO list the original factory specs for everything - which can also be a big drawback as over time the factory changes specs. But usually when buying parts, if a spec has changed, they include papers with the parts that list what models those specs had changed on. Might want to think about picking one up some day, they aren't that cheap, but they are a very valuable resource to have if you plan on keeping a vehicle for more than a year or two.
As for your wifes car, if it has ultra high compression, or a really fancy ignition system, it could very well take into account fractions of a degree for fuel temp to measure out very precise amounts of fuel, or even adjust the voltage for firing the plus, or if it has VVT of some form, adjust that for a slightly different burn. Manufactures are having to measure every potential variable these days because of increases in required fuel economy from the government. So IF you have a fuel temperature probe that's not measuring right, consider replacing it at some point in the near future, heck, even an air intake temp sensor can allow a car to run, but throw fuel mileage off. Our 97 towncar (it's in rough shape now though) had a fault air intake temp sensor, couldn't get above 18mpg, and wasn't triggering the CEL. Replaced that, now it gets upwards of 24mpg, and that's on an old big v8 engine. Wouldn't think it matters much since it has a MAF, but it really does.
ANYWAYS, let me know what you DO find, and depending on whats found, I will post up how to check the "timing" for the ignition. Rather stupid they used that method to time the spark, but I guess it's an old tested method that just works if you have ever messed with such things.
If you could get me a good picture of the engine bay from an overhead position, I would know for sure what kind of ignition system you have, pretty sure it's EDI from your description.
Aside from ignition related components, we could have an issue with proper fuel delivery, but I would prefer all electrical components on the spark side are operational before we poke at possible fuel delivery issues.
BTW, while most hate Haynes booklets, I find they are rather great to have handy because they DO list the original factory specs for everything - which can also be a big drawback as over time the factory changes specs. But usually when buying parts, if a spec has changed, they include papers with the parts that list what models those specs had changed on. Might want to think about picking one up some day, they aren't that cheap, but they are a very valuable resource to have if you plan on keeping a vehicle for more than a year or two.
As for your wifes car, if it has ultra high compression, or a really fancy ignition system, it could very well take into account fractions of a degree for fuel temp to measure out very precise amounts of fuel, or even adjust the voltage for firing the plus, or if it has VVT of some form, adjust that for a slightly different burn. Manufactures are having to measure every potential variable these days because of increases in required fuel economy from the government. So IF you have a fuel temperature probe that's not measuring right, consider replacing it at some point in the near future, heck, even an air intake temp sensor can allow a car to run, but throw fuel mileage off. Our 97 towncar (it's in rough shape now though) had a fault air intake temp sensor, couldn't get above 18mpg, and wasn't triggering the CEL. Replaced that, now it gets upwards of 24mpg, and that's on an old big v8 engine. Wouldn't think it matters much since it has a MAF, but it really does.
ANYWAYS, let me know what you DO find, and depending on whats found, I will post up how to check the "timing" for the ignition. Rather stupid they used that method to time the spark, but I guess it's an old tested method that just works if you have ever messed with such things.
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