20 Most Recent 1991 Porsche 928 - Page 9 Questions & Answers

No. But before installing the injectors in the fuel rail fitting submerge the ends of the injectors with the seals completely in some perfectly clean fuel.. Make sure the seals are wet with fuel and then install them and they should slide into position easily and will not leak. =============================================

Porsche Becker radio codes emailed to you from the serial number here: Car Radio Codes United Kingdom Gumtree

If you are a two footed driver or use the accelerator while the brake is applied, the DME module will cause a reduction in power producing a lag

Abel, yes, safety feature just in case it didn't happen to be all the way in neutral.

TPS sensor(RPM)

Under dash

Not much left unchanged is there and no doubt you have done compression testing on all 4 cylinders as well. (If not you need to). I assume it is cranking over normally with the starter motor but not firing. I would try one of the Porsche Owners Forums for this as one of the other 944 owners there should be able to help..... Like this one.................. Porsche 924 944 968 Technical Forum Pelican Parts Technical BBS

First thing to check, pull the distributor cap off and make sure the rotor is still screwed to the shaft, they had a bad habit of getting loose, it also gives you a chance to make sure the cam is turning. Next I'd just replace the DME relay because they commonly caused this problem, then check the output of the reference sensors with an analog voltmeter on the lowest scale - you're looking for 2v blips, also confirm 12v at the coil with the ignition on. If you have all that you may need to pull the DME out and re-solder the connections from the big power transistor to the pc board, they crack over time.

You have to buy or borrow a compression gauge tester. It threads into the spark plug hole; so you pull all the plugs out, then check each cylinder's compression. The proper way is to first disable gas and spark, put the tester into the first cylinder, then crank the engine over a set number of times- the same amount of cranking for each cylinder, so all get a balanced test. While cranking, hold the accelerator pedal all the way to the floor-this lets the engine breathe normally, getting all the air available. then compare your compression readings: a good healthy engine will have all cylinders pretty even, in the range of somewhere between 150 psi-200 psi. Low compression readings means compression is being lost somewhere, like worn piston rings, bad head gasket seal, or valves not sealing. Wondering if you have any compression at all? Hold your finger over a spark plug hole while someone briefly cranks the engine over. You can tell if there's any compression at all-you will feel the pressure build up under your finger. Rent or buy the gauge tester to get a true reading of your compression.

Was the relay the problem or is the pump bad. All to often I've seen the connector pins making a bad connection. If you need further help, reach me via phone at https://www.6ya.com/expert/chris_b82b45c59bcf133d

No,they should be good.

Could be bad battery or connection.Check fuel filter.

You probably moved a vacuum hose out of place, or your Idle Air Control Valve is failed, but there could be more. Watch the following video to get an idea about the Idle Air Control & Fast Idle Air. https://www.youtube.com/watch?v=L788jKEVblY

A lot of issues with that 4.8, customer of mine replaced o2 sensors, 300 or 308 are present also must look after them first Possible fault causes - Valve(s) of a cylinder stay jammed in large stroke - Valves of different cylinders stay jammed in large stroke -parity check error

have it rebuilt by a competent shop, but you can probably replace it with a good salvage yard unit cheaper. Also, shy was it out of fluid?