[kevgore55]

Help please new owner
I have just got a 220gti ( mattewsens october auction) its a decent car with only a few small rust scabs around the wheel arches and the usual rear sill
problem which have been repaired and painted with a different silver paint so some paint is needed
I have a problem with temp gauge it works while stationary with the engine running at around 1/3 to 1/2 on the the gauge the problem is when driving the temp gauge falls to zero but will rise again when stopped for a while in traffic. The fan cuts in at 1/2 gauge i assume the temp sender is faulty or possibly the thermostat is stuck closed ( unlikely as i drove the car home 180 miles from the auction)
I assume the water temp sender and the fan sensor are the two sensors connected into the thermostat housing is this correct or are they elsewhere?
I also have no heat coming out of the heater matrix either. The cooling system appears to be full as the header tank is at max level i see there is some sort of matrix to feed the heater with some sort of valve does anybody know what it is and how it works ?
I also need a wiring diagram so i can work out what else is not working as the engine bay fuse box is missing several fuses and some of the relays at present the rear demist, rear wash wipe, and the door mirror demisters do not work.
Thanks in advance for any help in advance
kevan

[Johnny 216GSi]

I reckon that could be your thermostat.

It's not stuck closed. That would cause an engine overheat and a rising temperature on your gauge.

It's sticking open, hence the engine is cooling too much and the temp gauge is dropping down. When you're stationary, there's a loss of air flow to the radiator, so the temp is rising again.

Depends on mileage, but a yardstick is usually around the 100K mark. Problems can occur just with age, e.g. 25+ years and higher.

An easy fix. Just get a decent replacement thermostat.

If it's a T-series engine, it's part code PEL10017P, item 15 on this page: https://rimmerbros.com/Item--i-GRID002427 or part code 13H7604 if your car doesn't have air con. Item 12 on this page: https://rimmerbros.com/Item--i-GRID002428. I know part code 13H7604 fits both M and T series engines. Not sure at all about PEL10017P.

[220 GSi turbo]

I've just had a look at the Mathewsons results page and it looks like you have got yourself a really nice car there at a very good price!

If you decide to join the club, you will have access to download a wide range of scanned Rover workshop manuals including the electrical wiring diagrams

[kevgore55]

I reckon that could be your thermostat.

It's not stuck closed. That would cause an engine overheat and a rising temperature on your gauge.

It's sticking open, hence the engine is cooling too much and the temp gauge is dropping down. When you're stationary, there's a loss of air flow to the radiator, so the temp is rising again.

Depends on mileage, but a yardstick is usually around the 100K mark. Problems can occur just with age, e.g. 25+ years and higher.

An easy fix. Just get a decent replacement thermostat.

If it's a T-series engine, it's part code PEL10017P, item 15 on this page: https://rimmerbros.com/Item--i-GRID002427 or part code 13H7604 if your car doesn't have air con. Item 12 on this page: https://rimmerbros.com/Item--i-GRID002428. I know part code 13H7604 fits both M and T series engines. Not sure at all about PEL10017P.

Thanks for the information i have an m series engine so the 13H7604 is the thermostat i need hopefully that will give me a working temp gauge when the car is at normal road speed and not just when idling stood still

[kevgore55]

I've just had a look at the Mathewsons results page and it looks like you have got yourself a really nice car there at a very good price!

If you decide to join the club, you will have access to download a wide range of scanned Rover workshop manuals including the electrical wiring diagrams

Thanks for the heads up i have joined the club and can now access to all the manuals the earlier R8 200GTI 20M4F series engine appears to be missing i can only find the later T series engine with vin numbers from 605482 i assume they are more or less the same ?

[alviseven]

sounds to me like someone might have been naughty and removed the thermostat completely perhaps to disguise overheating issue. Had similar symptoms on astra estate