Attachment Bulletin # 159902

Group: 15

Number: 99-02

Date: Aug. 11, 1999

Subject:
Engine Cranks But Will Not Start

Model(s):
A4 with 1.8L Turbo 1997, 1998, 1999

Condition

Engine cranks but will not start.

When procedure applies to vehicles within the New Vehicle Limited Warranty, use the following:

Part Identifier: 1500

Labor Operation: 1500710 85 TU

Does not include:

Decarbonation/ 1560561 75 TU
Oil change

To claim Wynn's V.I.C.: Place $15.96 U.S. (Canada at current exchange rate) in the Subjet Parts Field of the Warranty Claim.

Service

Perform the following:

- Connect VAG 1551 scan tool.

- Select Address word 01 "Engine Electronics".

- Select Function 08 "Read measuring value block".

- Read and print measuring value blocks 4, 6, 32, 55 and 60.

- Check for Diagnostic Trouble Codes (DTC's) stored in DTC memory.

- Print any stored DTC's.

- Take corrective action for any stored DTC according to the DTC table in the OBD II Fuel Injection & Ignition section of the 1.8 Liter 5V Repair Manual.

Note:
In most cases no DTC's will be found.

- Check for correct fuel level (vehicle must not be out of fuel).

After vehicle sits for minimum several hours (preferably overnight):

- With ignition switched ON.

- Check engine coolant temperature sensor for reasonable values in measuring value block 4 (must read approx. ambient temperature).





- Check altitude sensor in measuring value block 6 for reasonable values (according to the altitude for your geographical location) per table.

- Check throttle body for proper mechanical function.

^ Must operate smoothly between closed and wide open throttle.

- Crank engine while observing throttle angle specifications in measuring value block 60.

^ Throttle angle must be greater than 6°.

- Check and record fuel pressure.

- If coolant temperature sensor, altitude sensor, throttle body and fuel pressure are OK:

- Remove and inspect all spark plugs.

If wet allow to dry. If fouled, replace as necessary.

- Perform a compression test and cylinder leakage test on all cylinders (record results).

Note:
Low compression may indicate carbon particles are present on the intake and/or exhaust valves and in the combustion chamber (causing the valves not to seat properly).

If compression and leak check are OK:

- Contact the Dealer Technicians Helpline.

If compression and leak check are not OK:

- Disconnect injector wiring and crank engine for minimum of 30 seconds.

- Reconnect injector wiring.

- Install spark plugs.

- Depress throttle and crank engine until engine starts then switch ignition OFF.

- Following instructions in the kit, use Decarb Tool kit US 9025 along with Wynn's(R) X-Tend(R) V.I.C. Combustion Chamber Cleaner: Part No: 61510 (U.S.), Part No: 61512 (Can.) to remove carbon deposits.

- It will also be necessary to change engine oil after carbon removal. (Oil filter not required).

Wynn's(R) V.I.C. can be obtained through your local Wynn's(R) Oil representative. For your local Wynn's Oil representative call 1-800-98X-TEND.

Caution!
Use of any other cleaning fluid could damage emissions components, use only Audi approved Wynn's V.I.C.

Be sure to attach a copy of the 1551 print-out to the work order for future verification.

Note:
Customers should be made aware that this type of carbon build-up may be due to fuels that do not contain a sufficient blend of detergents. Customers should be given the brochure "Facts about Carbon and Fuel Quality" (Literature No. W425527100) and advised to use Autobahn Gasoline Additive (ZVW 239 003) which is very effective in reducing and preventing carbon buildup even if the fuel used does not contain a sufficient blend of detergents.

Note:
Perform the following only with a fully charged battery

- Start engine (if necessary Depress throttle fully and crank engine until engine starts). Continue to run engine until warm.

With engine fully warmed:

- Road test vehicle under load with engine between 4000 to 6000 RPM's for approx. 10 miles (use appropriate lower gear to stay within legal speed limits).

Procedure is complete.