m104
 

I have a 99 s320 that has no codes to help me repair it.Problem will not accept full throttle,wants to back fire with pedal pressed more.
New parts fuel filter and pump,oxygen sensor,MAF,coils,plugs,wires,battery,ignition switch,k38 relay,and no cats.
what else is there crank sensor? It couldn't be cam sensor as it has perfect idle.could injectors do this,or would they throw a code?oh yes no cats to clog.between 45 and 55 mph,idle or rpms dive 400 rpms in drive at between 60c and 78c

I wouldn't throw any more parts at it. I would be looking at fuel pressure, injectors, throttle body, but probably worth just paying for a diagnostic if you don't have a capable scanner yourself.

I ran a scanner no codes

Just the standard $39 scanner for codes? I mean like the DAS Xentry or similar, with live data.

I had a W124 E320 that had similar issues. It was a bad intake manifold gasket.

I ran a $1500. scanner from Snap on.What should be proper vaccum reading?is it possible to pressurize the intake manifold and vac ports to spot a leak?Or can I take a cigar and blow into vac line. My engine changed idle when I used a sprayer to check for leaks.But I don't know where

Then you clearly have a vacuum leak which is a problem...unmetered air.

you mean a little leak would cause all of this?Tell me what a vac gauge should read I will rent one too.

Use your mightyvav !

my glass dial fell off my mighty vac,will it still work.I have not used it or one before

Dont know, try it

what should I do about the throttle body to seal it off,a rubber glove?Then vacuum intake to listen for leaks

I used a rubber glove
 

I put engine under vac,and found two bad leaks,however did not fix the car.I have 19psi as I used a boost vac gauge to measure vacuum.

How are your fuel trims at 2000 and 3500 rpms?

Hirnbess what do you mean trims,I had to borrow fuel pressure gauge.I had 62 psi while it was poping,and acting like it had no fuel.I'm begining to think I have a couple of bad injectors,or they need cleaning by hand.Had two bad vacuum leaks fixed and now at certain temps when warming up idle fluctuations is worse.Was diving 200 rpm now 400.I think the idle flucts. and even in drive are related
Its funny also I can hit 3000 rpm in first but only 2500 in second. I did make the mistake of oiling my TPS. I notice engine at between 45 and 55.But when I drive at greater load it stops.

check the fuel trims and air mass movement. A leaky intake manifold will cause some really serious problems in any engine.

yes I know I used a boost gauge to measure vacuum 19 psi.Much stronger after I fixed two leaks

The fuel trims, shown on the scanner, are what the ECU is thinking the mixture is. If it's thinking rich, then a signal is telling it that the mixture is too rich which would point to the MAF. I know you changed that, but it is a common culprit with no codes. Maybe you could swap the old one back in to see if there's any change at all.
Clogged injectors? Possibly, but it sounds very rare.

my friend that was using the scanner (a $5000 unit) was watching fuel trims,I remember that page as she was running how ever she was not under load.Could my ecm be bad?the old MAF car idle would not change when you unplugged it,this one does,she runs much better under 3000 rpms.Quicker,just won't go past it.Found two owners on the net with same problem,one replace the TPS,the other crankshaft sensor.As stated before I made the mistake of lubing my TPS with wd40.Thought it would solve the squeek.

Could be the ECU, could be the TPS, and really it could be a lotta things. But with no codes to guide us, it can be an expensive game of hit or miss.
If it was me, at this point I would double check all vacuum lines (I remember especially those ones up under the intake manifold, and the junction at the front of the engine) and then just drive it for awhile, trying to force a code.
If nothing comes back, and pride prevents a trip to the dealer for a diagnosis, I would probably swap the TPS first, based on cost.

I will replace CPS and TPS then go to a good indepent shop.that way I saved them and myself from mark up on parts