# 1971 Volvo P1800 TPS **URL:** \ **Category:** Power/Fuel\ **Tags:** coupe, volvo, gasoline\ **Created:** [July 2, 2010, 6:02pm UTC](https://community.cartalk.com/t/1971-volvo-p1800-tps/51190 "2010-07-02T18:02:45Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![gjreed](https://avatars.discourse-cdn.com/v4/letter/g/dfb087/32.png) [@gjreed](https://community.cartalk.com/u/gjreed)\ **Post date:** [July 2, 2010, 6:02pm UTC](https://community.cartalk.com/t/1971-volvo-p1800-tps/51190/1 "2010-07-02T18:02:45Z")
So I’ve been having an issue with the throttle on my p1800. It starts right up, but to keep it running I have to feather the throttle for at least 10 mins. To make the engine rev higher I have to feather it harder. It has a Bosche injection system on it mostly original. I have replaced the fuel filter, pressure regulator, had the pump serviced, replaced the fuel pump relay, and had the computer control looked at by a mechanic, who said it looked fine but seemed unsure. The only thing I can think of is the Throttle Position Sensor, but I cannot find them for sale anywhere. Any ideas would be awesome. Thanks Garrett ---
**Author:** ![texases](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/texases/32/862_2.png) [@texases](https://community.cartalk.com/u/texases)\ **Post date:** [July 2, 2010, 6:05pm UTC](https://community.cartalk.com/t/1971-volvo-p1800-tps/51190/2 "2010-07-02T18:05:59Z")
Does it have a TPS? I’d have thought it has Bosch Jetronic (of some vintage) FI, which is largely mechanical. If this problem goes away once it’s warm check if there’s a cold start injector, maybe something wrong with that. Also, that’s a very popular car with Volvo folk, I bet you’d get a quick answer on one of the P1800 forums (google it). ---
**Author:** ![gjreed](https://avatars.discourse-cdn.com/v4/letter/g/dfb087/32.png) [@gjreed](https://community.cartalk.com/u/gjreed)\ **Post date:** [July 2, 2010, 6:09pm UTC](https://community.cartalk.com/t/1971-volvo-p1800-tps/51190/3 "2010-07-02T18:09:20Z")
It does have a TPS attached to the Throttle body which regulates the amount injected. I changed the cold start sensor, and cleaned the cold start injector, which is a small port in the air intake. ---
**Author:** ![texases](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/texases/32/862_2.png) [@texases](https://community.cartalk.com/u/texases)\ **Post date:** [July 2, 2010, 6:11pm UTC](https://community.cartalk.com/t/1971-volvo-p1800-tps/51190/4 "2010-07-02T18:11:28Z")
OK. But is it only a cold start issue? If it is, I have trouble seeing how the TPS would be the problem. ---
**Author:** ![gjreed](https://avatars.discourse-cdn.com/v4/letter/g/dfb087/32.png) [@gjreed](https://community.cartalk.com/u/gjreed)\ **Post date:** [July 2, 2010, 6:14pm UTC](https://community.cartalk.com/t/1971-volvo-p1800-tps/51190/5 "2010-07-02T18:14:41Z")
No, I have to feather it for at least the first 10 mins even if its a warm restart. ---
**Author:** ![Rod-Knox](https://avatars.discourse-cdn.com/v4/letter/r/a183cd/32.png) [@Rod-Knox](https://community.cartalk.com/u/Rod-Knox)\ **Post date:** [July 2, 2010, 6:31pm UTC](https://community.cartalk.com/t/1971-volvo-p1800-tps/51190/6 "2010-07-02T18:31:16Z")
I believe the TPS functioned only to indicate that the throttle was released, signaling the computer to take over the idle speed. ---
**Author:** ![gjreed](https://avatars.discourse-cdn.com/v4/letter/g/dfb087/32.png) [@gjreed](https://community.cartalk.com/u/gjreed)\ **Post date:** [July 2, 2010, 6:59pm UTC](https://community.cartalk.com/t/1971-volvo-p1800-tps/51190/7 "2010-07-02T18:59:48Z")
So the issue may be in the idle control. Okay I’ll check that out. Another thing is that if I disconnect the temp sensor for the injection system the problem seems less sever.