Using diesel,kerosene or steam for external car cleaning

[Atif]

Recently, I was advised to have my Camry 2006 engine steam washed. In the past I have stuck to the advice of not allowing Diesel used to clean the engine and undercarriage. The rationale behind this is that diesel will attract sand and mud to stick, making it worse in the long run. Apart from this the agency service never did this. However, I have faced instances of deliberate use of diesel even after instructing the car wash guy not to.

My question is this, what is the best form of cleaning if being done on a very dirty engine and under carriage?

[Srikumar]

From what I understand, steam wash is the best that you can do for your car. Diesel does affect the life of rubber and I am not sure if it should be used. But it does help with removing of all the squeaky noise.

[Rahimdad]

Totally agree with @Srikumar steam wash is the best. Full auto detailing even better. There are sprays in the US market to soften and rejuvenate rubber, not quite sure if I have seen any products here that would serve the purpose.

[desertdude]

Get an engine degreaser spray it liberally. Wait for it to do its thing and then rinse off. 

[Barry]

There is a product available called Gunk, google it. You spray it on, it foams up, then you pressure wash it off. It gets rid of all the oil and stuff. I used to use it to prep engines before car shows all the time. 

If you want to save money, but a 5 gallon jar of TFR, spray it on and wash it off. It’s like soap but stronger.