A/C & heat cause the engine to surge

[KYplumber]

When it was my money, I bought Snap-On. I'd rather have a used, semi-obsolete professional-grade scan tool than a brand-new consumer-grade tool, or a software-and-cable + laptop computer based tool.

I used a Snappy MTG2500 for near 20 years. Software good from 80 1/2 to 2005. When that croaked, I got a Snappy Solus Pro with software good from 80 1/2 to 2007. You'd need various OBD-1 cables (at least two, and preferably three for GM alone, a couple for Ford, some for Chrysler...you get the idea.) You'd want an OBD2 connector plus a fistful of "Personality Keys". Owner's manuals probably on DVD. Battery and charger, various other cables, and a bigass plastic suitcase to carry it around in.

Another forum member has donated an MT2500 for "community use". Maybe get yourself on the waiting list to borrow it. There's a sticky thread in the Engines forum.

Wholly cow! Almost sorry I asked ... Lol. But that's why I've always had my mechanic work on my truck... And trade out his needed plumbing repair. Missing that guy right now.... Lol

 

[Schurkey]

Wholly cow! Almost sorry I asked ...

Everything I mentioned cost me $350 shipped to my home. "New" it was ten times that amount, but it becomes very reasonable once the software is several years out-of-date, and the tool itself is discontinued in favor of a later generation unit. I also was able to use all the accessories from my previous MTG2500 that weren't included in the Solus Pro kit, since the Snappy accessories mostly carry-over from one generation of tool to the next.

 

[Nad_Yvalhosert]

The idle-up circuit is now functioning due to A/C compressor operation. But it's likely surging because there's carbon build up in said passages in the TBI unit.
Get to cleaning!

 

[Nad_Yvalhosert]

In post #2 @Schurkey overlooked it at first, then cicled back. Jen Psaki style!
Then @RichLo nailed it.

 

[KYplumber]

The idle-up circuit is now functioning due to A/C compressor operation. But it's likely surging because there's carbon build up in said passages in the TBI unit.
Get to cleaning!

Excuse my ignorance (I'm not a mechanic... Plumber by trade), is there a solvent used to clean this? It's a job I've never done, so imagine your speaking to a 6yo..... Lol.

 

[RichLo]

I like to use Seafoam Deep-Creep spray on the idle passage. You can start by spraying it while its running, then shut down and spray more and let it soak for 15mins, then fire up again and spray more. Drive it for a few miles after this to burn off all of the deposits.

If that doesnt help you can take the TBI off the truck and do a rebuild to really get into the passages.

If that still doesnt help you're IAC solenoid is probably sticking and you can replace it if your really that bothered by it.

 

[Schurkey]

I'd have used "Throttle Body Cleaner" which, as far as I can tell, is re-branded aerosol carb cleaner.

Examples:
www.amazon.com/CRC-05078-Throttle-Air-Intake-Cleaner/dp/B000M8PYO2/ref=sr_1_1

xc_hide_links_from_guests_guests_error_hide_media

and
www.amazon.com/Berryman-0110-Chemtool-Carburetor-Compliant/dp/B0167O869E/ref=sr_1_2

xc_hide_links_from_guests_guests_error_hide_media

And about two dozen similar products available at any auto-parts store in America, and most home-improvement/hardware stores.

You're buying an entire can, and cleaning the IAC passage is going to take about two three-to-five-second squirts into the oddly-shaped passage beside the main throttle bores.

That leaves the rest of the can to clean the throttle plates, throttle shafts, and the varnish and dreck that accumulates all over the throttle body--the air passages connected to the air cleaner or air cleaner elbow; and all the external surfaces as well. If you have a cable-operated throttle, open the throttle so you can spray the underside of the throttle plate(s). If the vehicle is throttle-by-wire, DON'T force the throttle open.

It'll probably take fresh paint off the intake manifold, somewhat less-active on old well-baked paint.

If you track down the SDS for any one of those throttle-body cleaners, you'll likely find that you can blend your own with various solvent-y, harsh, and cancer-causing chemicals such as acetone, xylene, naptha, MEK, and whatever else might be listed on the SDS. Don't blame me if you start growing a third arm out of the middle of your chest, or some gigantic tumor on your hands. You'll also have three or four gallons of mixture when you need ~16 ounces, so line up all your neighbor's cars and do 'em all at the same time.





Once upon a time, I looked-up the SDS (MSDS at that time) for the Seafoam products. While they were (deliberately) vague, it seemed like everything Seafoam made was the same end-product or at least similar, but packaged differently. Deep Creep aerosol, and the regular "metal-bottle, dump it in the engine" stuff used the same MSDS with minor variances.

Also--and I'm not absolutely sure about this--I remember going to a after-work seminar hosted by a local parts store, for professional techs. (This was 20+ years ago.) The presenter was a Seafoam representative, and he bragged-up how Seafoam would "melt away" carbon deposits in an engine, and to prove the point, he poured Seafoam liquid into a Styrofoam cup. The cup melted. How Styrofoam and carbon deposits are related, he did not explain.

NOW the company is claiming that Seafoam is "plastic safe" and it absolutely won't melt Styrofoam.

So I think they changed the formula for Seafoam "some time in the semi-recent past" while NOT telling anyone that it's totally different.

Seafoam sells a version of their product in an aerosol can (sorta like Deep Creep) but with an extra-long red plastic "straw" and angle-support thingie supposedly intended to clean the intake manifold beyond the throttle body. I've never used it.
www.amazon.com/Sea-Foam-Acting-Engine-Cleaner/dp/B015T5Y8CG/ref=sr_1_3

xc_hide_links_from_guests_guests_error_hide_media

You must be registered for see images attach

 

[KYplumber]

I like to use Seafoam Deep-Creep spray on the idle passage. You can start by spraying it while its running, then shut down and spray more and let it soak for 15mins, then fire up again and spray more. Drive it for a few miles after this to burn off all of the deposits.

If that doesnt help you can take the TBI off the truck and do a rebuild to really get into the passages.

If that still doesnt help you're IAC solenoid is probably sticking and you can replace it if your really that bothered by it.

Somehow just talking to you has helped... Lol. She ran better today than ever during the daily 40 mile commute. Probably unlikely it just took the ECM running time to adjust to the correction made by replacement of the alternator?..... Lol, it's a plumber joke. If it leaks long enough, maybe it'll seal itself.

 

[KYplumber]

I'd have used "Throttle Body Cleaner" which, as far as I can tell, is re-branded aerosol carb cleaner.

Examples:
www.amazon.com/CRC-05078-Throttle-Air-Intake-Cleaner/dp/B000M8PYO2/ref=sr_1_1

xc_hide_links_from_guests_guests_error_hide_media

and
www.amazon.com/Berryman-0110-Chemtool-Carburetor-Compliant/dp/B0167O869E/ref=sr_1_2

xc_hide_links_from_guests_guests_error_hide_media

And about two dozen similar products available at any auto-parts store in America, and most home-improvement/hardware stores.

You're buying an entire can, and cleaning the IAC passage is going to take about two three-to-five-second squirts into the oddly-shaped passage beside the main throttle bores.

That leaves the rest of the can to clean the throttle plates, throttle shafts, and the varnish and dreck that accumulates all over the throttle body--the air passages connected to the air cleaner or air cleaner elbow; and all the external surfaces as well. If you have a cable-operated throttle, open the throttle so you can spray the underside of the throttle plate(s). If the vehicle is throttle-by-wire, DON'T force the throttle open.

It'll probably take fresh paint off the intake manifold, somewhat less-active on old well-baked paint.

If you track down the SDS for any one of those throttle-body cleaners, you'll likely find that you can blend your own with various solvent-y, harsh, and cancer-causing chemicals such as acetone, xylene, naptha, MEK, and whatever else might be listed on the SDS. Don't blame me if you start growing a third arm out of the middle of your chest, or some gigantic tumor on your hands. You'll also have three or four gallons of mixture when you need ~16 ounces, so line up all your neighbor's cars and do 'em all at the same time.





Once upon a time, I looked-up the SDS (MSDS at that time) for the Seafoam products. While they were (deliberately) vague, it seemed like everything Seafoam made was the same end-product or at least similar, but packaged differently. Deep Creep aerosol, and the regular "metal-bottle, dump it in the engine" stuff used the same MSDS with minor variances.

Also--and I'm not absolutely sure about this--I remember going to a after-work seminar hosted by a local parts store, for professional techs. (This was 20+ years ago.) The presenter was a Seafoam representative, and he bragged-up how Seafoam would "melt away" carbon deposits in an engine, and to prove the point, he poured Seafoam liquid into a Styrofoam cup. The cup melted. How Styrofoam and carbon deposits are related, he did not explain.

NOW the company is claiming that Seafoam is "plastic safe" and it absolutely won't melt Styrofoam.

So I think they changed the formula for Seafoam "some time in the semi-recent past" while NOT telling anyone that it's totally different.

Seafoam sells a version of their product in an aerosol can (sorta like Deep Creep) but with an extra-long red plastic "straw" and angle-support thingie supposedly intended to clean the intake manifold beyond the throttle body. I've never used it.
www.amazon.com/Sea-Foam-Acting-Engine-Cleaner/dp/B015T5Y8CG/ref=sr_1_3

xc_hide_links_from_guests_guests_error_hide_media

You must be registered for see images attach

I ddddd.. DON'T need any more chhhhemicals.
But I understand completely what you're saying. It really irritates a plumber that chemical drain cleaners (liquid plumber, Draino ... Etc) are allowed to print "will not harm your pipes" on the package when we earn 1/3 of our profit replacing plumbing damaged by those products. But it might hurt sales if the said, "can cause severe chemical burns, respiratory issues, and won't do **** to clear the blockage"... Lol.

That being said, I'd like to hear your professional opinion on leak sealers poured into the engine. Daughter's BF bought main seal leak sealer for a small leak he believes is coming from the rear seal. I told him I would pour anything into his engine without talking to a pro first.

 

[RichLo]

That being said, I'd like to hear your professional opinion on leak sealers poured into the engine. Daughter's BF bought main seal leak sealer for a small leak he believes is coming from the rear seal. I told him I would pour anything into his engine without talking to a pro first.

I could be wrong about this but I have always heard that leak sealing additives purposely degrades the rubber causing them to get softer and expand which then seals the leak. This works for a period of time until the rubber completely breaks down and then you have a leak 10x worse than what you started with.