Cause
Missing or perished warm air duct
The duct carrying warm air from the exhaust manifold shroud to the air cleaner, missing or perished. It is usually a flexible foil or paper hose that embrittles with heat and is frequently thrown away rather than replaced.
Without it the intake can only draw cold air, so the temperature control system has nothing to select and the module reports that intake temperature is not responding as commanded. The practical symptom is poor cold-weather driveability — hesitation and stumbling until the engine is thoroughly warm — which is easy to attribute to fuelling. Check the duct exists and is connected at both ends; it is often found lying in the engine bay or absent altogether after earlier work, and the manifold shroud it connects to may also have corroded away.
Typically an easy fix. Often worth checking before paying anyone to look.
Codes this can cause (1)
Codes where this is a likely explanation first, rather than merely a possible one.
Information, not instruction
CarGeek is a reference, not a service manual. Its pages are written from public sources and from what other people have found, never from a manufacturer's own service information, so they can be wrong or incomplete for your particular vehicle. Some of what they describe carries real risk: high voltage, fuel under pressure, stored energy, hot and moving parts.
Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
Others who found this
Be the first to write this up
Nothing posted about this yet. Whatever you found is worth writing down — even a dead end saves someone the same afternoon.
What makes one worth reading:
- The car — make, model, year and engine. The same fault behaves differently on each.
- What you measured, not only what you replaced.
- What actually fixed it — or that nothing did, which is worth knowing too.
Sign in or create an account to add what you found about Missing or perished warm air duct.